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mathcalculus
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PLEASE HELP :( !!
y=13e^(3x^2)6x
at x=3 in the form y=mx +b has
 11 months ago
 11 months ago
mathcalculus Group Title
PLEASE HELP :( !! y=13e^(3x^2)6x at x=3 in the form y=mx +b has
 11 months ago
 11 months ago

This Question is Closed

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
f'(x)= 78xe^(3x^2)6
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
slope= 234e^276 y=13e^2718
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
So you're looking for an equation of the line tangent to the curve f(x) at x=3?
 11 months ago

akotto4897 Group TitleBest ResponseYou've already chosen the best response.0
omg this is so simple
 11 months ago

akotto4897 Group TitleBest ResponseYou've already chosen the best response.0
wat is america coming to
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
yes, Determine the equation of the line tangent to the graph of
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
yeah but I'm not sure why I'm getting this wrong.
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
@akotto4897 wtf is wrong with you? Why would you call someone elses problem `so simple`. It's like someone in 5th grade calling 3rd grade math SUPER EASY! Just because you understand it doesn't mean that everyone else is on your level...
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
Ok that's enough of my rant :) lemme check your work a sec :3
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
lol, i appreciate that. but yes, let's begin.
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
Mmm ok so your slope looks good. So what coordinate pair are we using to find our yintercept?\[\Large f(3)\quad=\quad 13e^{27}18\]Mmm ok ok I see you have the written down already :3 \[\Large y_{\tan}\quad=\quad mx+b\]So if we plug in our coordinate pair, we get something like this, yes?\[\Large 13e^{27}18\quad=\quad (234e^{27}6)\cdot 3+b\]
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
woah so the slope is good and the y too.
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
oh i see there's an x there.
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
so would it be 247e^2718?
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
for your y_tan? or for b?
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
y tan
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
Hmm after you find your b value, you should plug it back into the \[\Large\bf y_{tan}\quad=\quad \color{royalblue}{m}x+\color{royalblue}{b}\] For our final answer, we DON'T want the coordinate pair plugged in. We're only trying to fill in these blue pieces.
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
so how do i get to the answer.
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
at first i thought it was 247e^27 6x
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
grr sorry website crashed on me >:c
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
its fine
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
i just don't understand what to do at the point slope formula.
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
i keep getting the answer wrong.
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
\[\Large\bf y_{\tan}\quad=\quad \color{royalblue}{m}x+\color{royalblue}{b}\]Plugging in our slope,\[\Large\bf y_{\tan}\quad=\quad \color{royalblue}{(234e^{27}6)}x+\color{royalblue}{b}\]Then we plug in our coordinate pair to find b,\[\Large\bf \color{#DD4747 }{13e^{27}18}\quad=\quad \color{royalblue}{(234e^{27}6)}\cdot\color{#DD4747 }{3}+\color{royalblue}{b}\]
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
So we have some 18's cancelling out. And I think we get a b value of,\[\Large\bf \color{royalblue}{b\quad=\quad 689e^{27}}\]Something like that?
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
isn't it y(13e^2718)=234e^276x+18
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
right, yy1=m(xx1)
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
so in this case, slope= 234e^276 y=13e^2718
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
and x1= 3
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
No that's `pointslope` form of a line. yy1 = m( xx1) We don't want to use that. We were told to use the `slopeintercept` form of a line. y=mx+b
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
can we do it the way i had it please?
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
yeah but i thought i could use that to find the equation of a tangent line
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
I've been using that for other problems and it worked.
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
Yes we can use that, so let's see if we can get it set up correctly. Lemme see if I can match what you wrote a sec :)
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
\[\Large\bf yy_1\quad=\quad \color{royalblue}{m}(xx_1)\]\[\Large\bf yy_1\quad=\quad \color{royalblue}{(234e^{27}6)}(xx_1)\]Then plugging in our point:\[\Large\bf y\color{#DD4747 }{(13e^{27}18)}\quad=\quad \color{royalblue}{(234e^{27}6)}(x\color{#DD4747 }{3})\]
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
yes correct! :)
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
after that I'm lost lol
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
Ok so now we just need to get in into the form y=mx+b. So we need to multiply out the brackets, then we gotta isolate the y term.
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
\[\large\bf y\color{#DD4747 }{(13e^{27}18)}\quad=\quad 234e^{27}x6x 702e^{27}+18\]I think it expands like that, yes? Give it a try :)
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
yup, but i seem to be doing that wrong unfortunately.
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
wait don't we just multiply out the 6 and 6*3 only?
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
and leave the
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
Yes, true. We probably want don't want the x's expanded like that,\[\large\bf y\color{#DD4747 }{(13e^{27}18)}\quad=\quad (234e^{27}6)x 702e^{27}+18\]
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
\[\Large 234e^{27}\cdot3\]
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
why don't we multiply 234e^27 with x?
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
and then 3
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
\[\large\bf (234e^{27}6)(x3)\quad=\\ \large\bf\quad (234e^{27}6)x(234e^{27}6)3\]And we only want to multiply out the part with the 3.
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
im so confused. i do't understand why we did this problem differently than all the others when it comes to this part.
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
so for (234e^27−6)(x−3) i thought we do foil
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
Yes, foiling should give you this,\[\large\bf 234e^{27}x6x 702e^{27}+18\]
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
Are you not getting that when you foil..?
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
yes i have that! :)
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
We don't want multiple x terms, so we'll factor an x out of each of the first two terms.\[\Large\bf =\quad \large\bf (234e^{27}6)x 702e^{27}+18\]
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
now what? :(
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
where does my foiling go?
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
great so we factor?
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
We had this,\[\Large\bf y\color{#DD4747 }{(13e^{27}18)}\quad=\quad \color{royalblue}{(234e^{27}6)}(x\color{#DD4747 }{3})\]It foiled to give us this,\[\large\bf y(13e^{27}18)\quad=\quad 234e^{27}x6x 702e^{27}+18\]We factored out an x to give us this,\[\large\bf y(13e^{27}18)\quad=\quad (234e^{27}6)x 702e^{27}+18\]
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
We finish by solving for y.
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
right
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
x(468+12)
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
\[\large\bf y=\\\large\bf (234e^{27}6)x 702e^{27}+18+13e^{27}18\]
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
what..? :(
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
the 6 and the 18 are not like terms, we can't combine those.
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
I don't know why you insisted on using pointslope form for this one. It seems way more complicated :c
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
but it's the only way for me… i have to stick to this or else i'll be completely lost in the exam
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
This one only ended up being complicated because our slope was `2 terms`. So it ended up being a ton of multiplication.
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
damn im so confused.
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
what would be he answer btw?
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
\[\large\bf y(13e^{27}18)\quad=\quad (234e^{27}6)x 702e^{27}+18\]From here: you add (13e^{27}18) to each side,\[\large\bf y=\\ \large\bf(234e^{27}6)x 702e^{27}+18\color{orangered}{+(13e^{27}18)}\]Does that step make sense? +_+ That's how we isolate the y term.
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
From there we can drop the brackets since nothing in being applied to them, \[\large\bf y=\\ \large\bf(234e^{27}6)x 702e^{27}+18+13e^{27}18\]It looks like the 18's will cancel out,\[\large\bf y=\\ \large\bf(234e^{27}6)x 702e^{27}+\cancel{18}+13e^{27}\cancel{18}\]
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
And the exponential terms ( not the one attached to the x ) are like terms, so we'll combine them,\[\large\bf y=\\ \large\bf(234e^{27}6)x \color{orangered}{702e^{27}+13e^{27}}\] \[\large\bf y=(234e^{27}6)x \color{orangered}{689e^{27}}\]And I think that's our final answer, assuming I didn't make any boo boos along the way.
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
wait which is the mx and b?
 11 months ago

mathcalculus Group TitleBest ResponseYou've already chosen the best response.0
oh it is correct….
 11 months ago

zepdrix Group TitleBest ResponseYou've already chosen the best response.2
\[\large\bf y=\color{royalblue}{(234e^{27}6)}x \color{orangered}{689e^{27}}\]\[\large\bf y=\color{royalblue}{m}x +\color{orangered}{b}\]
 11 months ago
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