Recognize Identities: Recognize the trigonometric identities.We can use the Pythagorean identity sin2(x)+cos2(x)=1 to simplify the expression.
Use Pythagorean Identity: Rewrite the expression using the Pythagorean identity.We can replace sin2(x) with 1−cos2(x) in the expression cos3(x)+sin2(x)⋅cos(x).cos3(x)+(1−cos2(x))⋅cos(x)
Rewrite Expression: Distribute the cos(x) in the second term.cos3(x)+cos(x)−cos3(x)
Distribute cos(x): Combine like terms.The terms cos3(x) and −cos3(x) cancel each other out, leaving us with:cos(x)
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