C3 Differentiation

Hey Guys,

Could some one plz tell me how to start differentiating this 6sin^2(3x) should I use the chain rule or the product rule ? or even both ?!!

Thanx

Reply 1

zetamcfc

19

Original post by yoomi

Hey Guys,

Could some one plz tell me how to start differentiating this 6sin^2(3x) should I use the chain rule or the product rule ? or even both ?!!

Thanx

Try them and find out.

Reply 2

TeeEm

19

Original post by yoomi

Hey Guys,

Could some one plz tell me how to start differentiating this 6sin^2(3x) should I use the chain rule or the product rule ? or even both ?!!

Thanx

It definitely the chain rule
(the product rule though you can use in principle it is not sensible)

Reply 3

yoomi

OP

4

Original post by zetamcfc

Try them and find out.

I tried and I still getting different answer !

Reply 4

drandy76

13

Original post by yoomi

I tried and I still getting different answer !

working pl0x

Reply 5

PLM98

6

Put it in the form 6(sin(3x))^2 and then power comes down, subtract one from the power, multiply by the derivative of the thing in brackets (ie. sin(3x)) which is cos(3x) and multiply by the derivative of 3x, ie. 3, so you get 36sin(3x)cos(3x) and since we know that sin2A=2sinAcosA then we can simplify it to 18sin(6x)

Reply 6

yoomi

OP

4

Original post by PLM98

Put it in the form 6(sin(3x))^2 and then power comes down, subtract one from the power, multiply by the derivative of the thing in brackets (ie. sin(3x)) which is cos(3x) and multiply by the derivative of 3x, ie. 3, so you get 36sin(3x)cos(3x) and since we know that sin2A=2sinAcosA then we can simplify it to 18sin(6x)