Simplify (x+cos x)(cos x)-(1+sin x)(1-sin x)/(x+cos x)^2

Question

Please help me

Answer 1

Take (x + cos x)(cos x) − (1 + sin x)(1 − sin x) ÷ (x + cos x)² to

(x + cos x)(cos x) − (1 − sin²x) / (x + cos x)² and then to

(x + cos x)(cos x) − (cos²x) / (x + cos x)² and finally to

[(x + cos x)³(cos x) − cos²x]

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(x + cos x)²