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Sinx+2cosx-cos2x+cosx



User Xingdong
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1 Answer

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This expression can be simplified by using some trigonometric identities12. First, we can use the identity sin(2x) = 2sin(x)cos(x) to rewrite the first term. Then, we can use the identity cos(2x) = cos^2(x) - sin^2(x) to rewrite the fourth term. We get:

sin(x) + 2cos(x) - cos(2x) + cos(x) = 2sin(x)cos(x) + 2cos(x) - (cos^2(x) - sin^2(x)) + cos(x) = 2sin(x)cos(x) + 3cos(x) - cos^2(x) + sin^2(x)

Next, we can use the identity sin^2(x) + cos^2(x) = 1 to simplify the last two terms. We get:

= 2sin(x)cos(x) + 3cos(x) - cos^2(x) + sin^2(x) = 2sin(x)cos(x) + 3cos(x) - cos^2(x) + (1 - cos^2(x)) = 2sin(x)cos(x) + 3cos(x) + 1

This is the simplest form of the expression.

User Touhami
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