Mathematics
10 Online
OpenStudy (precal):
FTC part 2 given a graph
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (precal):
OpenStudy (precal):
I don't know what to do with this one. Should I just do what you taught me earlier?
ganeshie8 (ganeshie8):
#7 and #8 are area problems
ganeshie8 (ganeshie8):
#9 and #10 use FTC2
ganeshie8 (ganeshie8):
for #7 :
\[\large F(0) = \int \limits_{-6}^0 f(t) dt\]
Join the QuestionCove community and study together with friends!
Sign Up
ganeshie8 (ganeshie8):
find the area under curve f(t)
between x = -6 and 0
OpenStudy (precal):
ok I can do 7 and 8
OpenStudy (precal):
for 9 and 10 do I set it up like you showed me before
ganeshie8 (ganeshie8):
for 7 and 8 careful about the negative ares *
ganeshie8 (ganeshie8):
when the area is below x axis, integral is negative of Area
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (precal):
Thanks just notice that
OpenStudy (precal):
7 is -2pi +2
8 is -2pi +(1/2)
OpenStudy (precal):
not sure if I am doing 9 correct
OpenStudy (precal):
I got -8 for a solution but I did not use the graph at all. So I know I am incorrect
ganeshie8 (ganeshie8):
for #9 and #10 :
\[\large F(x)= \int \limits_{-6}^{2x}f(t) dt\]
\[\large F'(x) = \dfrac{d}{dx} \int \limits_{-6}^{2x}f(t) dt\]
\[\large = f(2x) (2x)'\]
\[\large = 2f(2x) \]
Join the QuestionCove community and study together with friends!
Sign Up
ganeshie8 (ganeshie8):
So,
\[\large F'(x) = 2f(2x) \]
OpenStudy (precal):
oh, I forgot to write f(2x)
ganeshie8 (ganeshie8):
just plugin x = -2, for #9
OpenStudy (precal):
is it -4?
ganeshie8 (ganeshie8):
Yes !
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (precal):
what about 11? 2nd derivative
do I just take the derivative of the above
ganeshie8 (ganeshie8):
we have : \[\large F'(x) = 2f(2x) \]
ganeshie8 (ganeshie8):
differentiate both sides with respect to x
ganeshie8 (ganeshie8):
\[\large F''(x) = 2f'(2x) \]
ganeshie8 (ganeshie8):
plugin x = 0
Join the QuestionCove community and study together with friends!
Sign Up
OpenStudy (precal):
shouldn't that be a 4 in front
OpenStudy (precal):
\[F"(x)=4f ' (2x)\]
ganeshie8 (ganeshie8):
thats a very good question, let me think a bit...
ganeshie8 (ganeshie8):
You're right ! we need to use chain rule and ithas to be 4f'(2x)
OpenStudy (precal):
cool, and my solution to 11 is 4
Join the QuestionCove community and study together with friends!
Sign Up
ganeshie8 (ganeshie8):
looks good :)
OpenStudy (precal):
thanks you make it look so easy and give me hope
ganeshie8 (ganeshie8):
np :)