Tunjukkan bahwa cosA/ 1 – tanA + sinA/1 – cotA = cosA + sinA

Penyelesaian:

(frac{Cos,A}{1 – Sin,A}+frac{Sin,A}{1-Cot,A}= Sin,A+Cos,A)

LHS = (frac{Cos,A}{1 – Sin,A}+frac{Sin,A}{1-Cot,A}) (LHS = frac{Cos,A }{1-frac{Sin,A}{Cos,A}}+ frac{Sin,A}{1-frac{Cos,A}{Sin,A}}) ( LHS = frac{Cos^{2},A}{Cos,A – Sin,A}+frac{Sin^{2},A}{Sin,A – Cos,A} ) (LHS = frac{Cos^{2},A – Sin^{2},A}{Cos,A – Sin,A}) (LHS = frac{(Cos, A + Sin,A)(Cos,A – Sin,A)}{Cos,A – Sin,A}) (LHS = (Cos,A + Sin,A)) = RHS

LHS = RHS

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