Question

Simplifique a expressão: Y= sen 31 . cotg 31 . cotg 59 . sec 59

Answer 1

Olá, Lya.

$Y=\text{sen }31\º\cdot\cot31\º\cdot\cot59\º\cdot\sec59\º=\\\\ =\text{sen }31\º\cdot\frac{\cos31\º}{\text{sen }31\º}\cdot\frac{\cos59\º}{\text{sen }59\º}\cdot\frac1{\cos59\º}=\\\\ =\frac{\cos31\º}{\text{sen }59\º}=\\\\ =\frac{\text{sen }(90\º-31\º)}{\text{sen }59\º}=\\\\ =\frac{\text{sen }59\º}{\text{sen }59\º}=\\\\ =1$