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anonymous
 one year ago
Find the equation of the line tangent to y = –x2 + 3x + 8 at x = 2.
anonymous
 one year ago
Find the equation of the line tangent to y = –x2 + 3x + 8 at x = 2.

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@dan815 could you help me?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0the derivative formula that I got is f'(x)= 6x+1

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0but none of the answers match my answer

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Find the equation of the line tangent to y = –x2 + 3x + 8 at x = 2. y = –2x + 2 y = –x + 12 y = –x + 2 y = –2x – 12

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0could you explain me how you got that answer

dan815
 one year ago
Best ResponseYou've already chosen the best response.3did you get the derivative function right

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0yes, because when I plug the value of 2 into my formula I get 1, which you presented me that it was correct, but I don't know how you got that formula

dan815
 one year ago
Best ResponseYou've already chosen the best response.3f'(x)= 6x+1 you said you got this, something wrong there

dan815
 one year ago
Best ResponseYou've already chosen the best response.3you have to differentiate term by term

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0never mind I got 2x+3

dan815
 one year ago
Best ResponseYou've already chosen the best response.3now you have a slope, then you find a point that belongs on this tangent line

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0but that doesn't have anything in common to the other answers

dan815
 one year ago
Best ResponseYou've already chosen the best response.3we know the x coordinate of the point,

dan815
 one year ago
Best ResponseYou've already chosen the best response.3now we find the y coordinate of the point and its part of the parabola so

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0do we plug it into the original formula or the derivate one?

dan815
 one year ago
Best ResponseYou've already chosen the best response.3we have the slope there, now we need to find the y coordinate then you will have a point and a slope and you figure out the equation of the line

dan815
 one year ago
Best ResponseYou've already chosen the best response.3the derivative formula only tells you the slope at every x value

dan815
 one year ago
Best ResponseYou've already chosen the best response.3we want to know the actual y point

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so which formula could I use to find the y value?

dan815
 one year ago
Best ResponseYou've already chosen the best response.3the tangent line intersects one point on the parabola, at x=2 and y is something, we can always find the y value for every x value on a parabola how?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0wait no, OMG I feel so ignorant.

dan815
 one year ago
Best ResponseYou've already chosen the best response.3y = –x^2 + 3x + 8 this equation of parabola

dan815
 one year ago
Best ResponseYou've already chosen the best response.3it gives you a y value for every x value

dan815
 one year ago
Best ResponseYou've already chosen the best response.3we know there is an intersection at x=2 so we have to see the y value there

dan815
 one year ago
Best ResponseYou've already chosen the best response.3y = –x^2 + 3x + 8 y=2^2+3*2+8 = 10

dan815
 one year ago
Best ResponseYou've already chosen the best response.3x=2,y=10 (2,10)dw:1436828495281:dw

dan815
 one year ago
Best ResponseYou've already chosen the best response.3now u have a point at the slope of the tangent line through that point

dan815
 one year ago
Best ResponseYou've already chosen the best response.3can you solve the equation of the line from here

dan815
 one year ago
Best ResponseYou've already chosen the best response.3y=mx+b m=1 lets plug in our point to see what b or the y intercept must be 10=1*2+b b=

dan815
 one year ago
Best ResponseYou've already chosen the best response.310=1*2+b 10=2+b b=10+2=12

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Oh i see I thought it was a 1 to the second power

dan815
 one year ago
Best ResponseYou've already chosen the best response.3this is the equation of a line y=mx+b

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0yeah, OMG I got it. Thank you so much. Could you help me with one more and thats it?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I already found that C actually has the value, but I don't know how to solve A nor B

dan815
 one year ago
Best ResponseYou've already chosen the best response.3this is the definition of a derivative

dan815
 one year ago
Best ResponseYou've already chosen the best response.3it is the equation to find the slope of a tangent line at x

dan815
 one year ago
Best ResponseYou've already chosen the best response.3it arises from taking a secant line where the points are getting closer and closer, lim h>0

dan815
 one year ago
Best ResponseYou've already chosen the best response.3for example take a look at any function f(x)

dan815
 one year ago
Best ResponseYou've already chosen the best response.3suppose you want to find the derivative at that point x for this function, you can begin to approximate by taking points close to that value because that is a close linear approximation

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okay, I see. I got 7 as the slope of the function

dan815
 one year ago
Best ResponseYou've already chosen the best response.3if we keep making h smaller and smaller then the point is close and closer to the actual tangent slope

dan815
 one year ago
Best ResponseYou've already chosen the best response.3well my work is done as long you understand how a derivative comes

dan815
 one year ago
Best ResponseYou've already chosen the best response.3its from this very simple concept, the slope of the tangent line at some point

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okay than you, I understood the secant and tangent line more.
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