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LagrangeSon678Best ResponseYou've already chosen the best response.1
come on no has helped you with this yet?
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
should i solve this or go to sleep.....
 2 years ago

ta123Best ResponseYou've already chosen the best response.1
solve before going, please
 2 years ago

ta123Best ResponseYou've already chosen the best response.1
Oops! forgot to sleep after going
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
okay, first things first, lets find the first derivaitve of the function your where given
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
can you find it?
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
now can you please evaluate: f(pi/4)=9sec^2(pi/4)
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
basically to make it more accesible we can write this as: f(pi/4)=9[sec(pi/4)]^2
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
further more we can write it as: f(pi/4)=9[1/cos(pi/4)]^2
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
then evalutaing we get: f(pi/4)=9[1/sqrt(2)/(2)]^2
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
further: f(pi/4)=9[sqrt(2)]^2 which the gives us: f(pi/4)=9(2), which is 18 Thus f(pi/4)=18
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
yes, look at the unit circle, at pi/4 or 45 degrees, cos is sqr(2)/2, now if we rationalize the numerator we get just sqrt(2)
 2 years ago

ta123Best ResponseYou've already chosen the best response.1
oh, thought your doing sec
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
i rewrote secx as 1/cosx
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
just to make is easier for me, but if realise that sec(pi/4) is sqrt(2) then more power to you
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
Now we have found the slope (m) of our line, it is 18
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
yes, but we will use this form, y=mx+b
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
i am getting sleepy lets finish this problem
 2 years ago

ta123Best ResponseYou've already chosen the best response.1
what would be the b in the slope formula
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
Now remeber we said, that we have the x coordinate in the beining of pi/4, lets evaluate the orginal function at this point, this will give us the y in our line. f(pi/4)=9tan(pi/4) =9(1) =9 now we have our x which is pi/4, we have our slope which is 18, lets plug this info into our line: 9=18(pi/4)+b this means that b is = to 918pi/4
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
now lets substitute everyting in: y=18x(3618pi)/(4)
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
i combined 9 and 18pi/4
 2 years ago

ta123Best ResponseYou've already chosen the best response.1
still don't see how you can 36??
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
dw:1316152625201:dw
 2 years ago

ta123Best ResponseYou've already chosen the best response.1
you could've just simplify it to 9pi/2
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
okay, then smarty pants do it your way, regardless we came to a correct answer
 2 years ago

ta123Best ResponseYou've already chosen the best response.1
sorry, so the finally would look like this 18x+9(1pi/2)
 2 years ago

ta123Best ResponseYou've already chosen the best response.1
I just look the answer choices and so which one was the closest, but how come they have it 18x+9(1pi/2) instead of just 18x+9pi/2
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
distribute the negative sign, first
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
dw:1316153351852:dw
 2 years ago

ta123Best ResponseYou've already chosen the best response.1
but was there a 918pi/4 at the beginning
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
can you not see it: dw:1316153548845:dw
 2 years ago

ta123Best ResponseYou've already chosen the best response.1
I meant why was 918pi/4 at the begginig
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
above i accidentally wrote:y=18x(3618pi)/(4), but is was really suppose to be : y=18x+(3618pi)/(4), sorry about the typo
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
okay, so can we lay this problem to rest?
 2 years ago

ta123Best ResponseYou've already chosen the best response.1
I guess, but still don't get why they have 918pi/4 plug into b instead of just 18pi/4 by itself
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
Now remeber we said, that we have the x coordinate in the beining of pi/4, lets evaluate the orginal function at this point, this will give us the y in our line. f(pi/4)=9tan(pi/4) =9(1) =9 now we have our x which is pi/4, we have our slope which is 18, lets plug this info into our line: 9=18(pi/4)+b this means that b is = to 918pi/4
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
dw:1316153804630:dw
 2 years ago

ta123Best ResponseYou've already chosen the best response.1
oh, ok now we can lay this problem to rest, thanks so much for being patience
 2 years ago

LagrangeSon678Best ResponseYou've already chosen the best response.1
its good you ask questions, i know i can confusing sometimes :)
 2 years ago

ta123Best ResponseYou've already chosen the best response.1
Thanks for giving me a metal
 2 years ago

ta123Best ResponseYou've already chosen the best response.1
yeah I just want to understand the problem instead of just getting the answer
 2 years ago

ta123Best ResponseYou've already chosen the best response.1
because I might see it on the test, but thanks again
 2 years ago
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