证明 (sin^2(x))/1*1/(sin^2(x))=1

解答

证明

\frac{sin ^{2} ( x )}{1} \cdot \frac{1}{sin ^{2} ( x )} = 1

真

求解步骤

\frac{sin ^{2} ( x )}{1} \cdot \frac{1}{sin ^{2} ( x )} = 1

调整左侧

\frac{sin ^{2} ( x )}{1} \frac{1}{sin ^{2} ( x )}

化简

\frac{1}{sin ^{2} ( x )} \frac{sin ^{2} ( x )}{1} : 1

\frac{1}{sin ^{2} ( x )} \cdot \frac{sin ^{2} ( x )}{1}

分式相乘:

\frac{a}{b} \cdot \frac{c}{d} = \frac{a \cdot c}{b \cdot d}

= \frac{sin ^{2} ( x )}{sin ^{2} ( x ) \cdot 1}

约分:

sin^{2} (x)

= \frac{1}{1}

使用法则

\frac{a}{1} = a

= 1

= 1

我们已展示，在两侧可以有相同的形式

\Rightarrow 真

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p ro v e cos (x + \frac{π}{6}) = \frac{3}{2} cos (x) - \frac{1}{2} sin (x)

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