# Thread: Integrate Trig. Mistake in Book???

1. ## Integrate Trig. Mistake in Book???

Hello All,

A problem in my calc. book asks to integrate [4 sin x + 2 cos x].

I get: -4 cos x + 2 sin x + C

The book, however, lists the answer as: -4 cos x + sin x + C

Is the book correct? I don't understand what happens to the 2 in '2 cos x', during integration.

Thanks,

InkHorn

2. Your answer is correct. It's probably a typo in the book.

3. Originally Posted by InkHorn
Hello All,

A problem in my calc. book asks to integrate [4 sin x + 2 cos x].

I get: -4 cos x + 2 sin x + C

The book, however, lists the answer as: -4 cos x + sin x + C

Is the book correct? I don't understand what happens to the 2 in '2 cos x', during integration.

Thanks,

InkHorn

4. ## Thank you

Originally Posted by drumist