Can someone help with this problem

[Jumpy Lee]

Homework Statement

Find the derivitive of y = (e^cx)(c sin x – cos x)

Homework Equations

None

The Attempt at a Solution

c(e^cx)(c sin x – cos x) + (c cos x + sin x)(e^cx)

The answer is { (1+c^2)((e^cx)sin x)

 

[TD]

The Attempt at a Solution

c(e^cx)(c sin x – cos x) + (c cos x + sin x)(e^cx)

The answer is { (1+c^2)((e^cx)sin x)

You're doing fine, they are the same! Try to simplify

 

[moe_3_moe]

it is right ... hey TD ..what he should simplify

 

[TD]

If you look well, you see the terms in cos(x) are opposite, they cancel out.

 

[moe_3_moe]

ah ok he did it ... i thought there is somethin' else i missed thanks for the reply

 

[Jumpy Lee]

Thanks TD i see how it works now

 

[TD]

You're welcome!

When you see that the given answer doesn't match your "longer" answer, always think of simplifying, it may just be correct after all !