Question

Differentiate the trig functions.

Answer 1

\[y=ccosx + x^2sinx\]

Answer 2

hey guys

Answer 3

im having trouble setting up the first part

Answer 4

I know ccosx= c(-sinx)

Answer 5

u know uv(product rule) in differentiation?

Answer 6

x^2sinx = x^2(cosx)

Answer 7

yes f(g)' + g(f)'

Answer 8

x^2sinx = x^2(cosx)<-------------nopes
u need to use uv rule there...

Answer 9

hmm uv?

Answer 10

uv or product....(fg'+f'g)
it will be x^2*cos x + 2x*sin x
ok?

Answer 11

where did you get 2xsinx?

Answer 12

ok, u know fg' + f'g
which function u took as f and which as g?

Answer 13

ccosx = f
x^2sinx = g

Answer 14

nopes, in x^2sinx
u take x^2 as f and sin x as g
then use f'g+fg'

Answer 15

ahhh ok, where does the ccosx go?

Answer 16

its till there and its diff -c sin x is also still there.....
-c sin x + f'g+fg'

Answer 17

sorry for the elementary questions, but why did we not call (ccosx) c = f and cos = g?

Answer 18

because c is constant when u differentiate w.r.t x
whereas both x^2 and sin x are functions of x.
constants can be taken out of differentiation.....

Answer 19

while using product rule f and g both must be functions of x

Answer 20

ok makes sense, thank you for your help. the c is the dead giveaway?

Answer 21

when you differentiate a constant doesent that leave you with zero?

Answer 22

yup, but here c is multiplied with cos x
so it just goes out of differentiation
so c* d/dx(cos x) = c*(- sin x)
which u already got.

Answer 23

if there was only c+...
then differentiation would be
0+d/dx(....)

Answer 24

ok cool thanks again!

Answer 25

so what u got as final answer?