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Math Help - Integrate Trig. Mistake in Book???

  1. #1
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    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
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  2. #2
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    Your answer is correct. It's probably a typo in the book.
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  3. #3
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    Quote Originally Posted by InkHorn View Post
    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
    Your answer is correct
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  4. #4
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    Thank you

    Quote Originally Posted by drumist View Post
    Your answer is correct. It's probably a typo in the book.
    Thank you very much drumist
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  5. #5
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    Thank you

    Quote Originally Posted by e^(i*pi) View Post
    Your answer is correct
    Thank you very much.
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