证明 (1-cos(x))*(1-cos(x))=(1-cos(x))^2

解答

证明

(1 - cos (x)) \cdot (1 - cos (x)) = (1 - cos (x))^{2}

真

求解步骤

(1 - cos (x)) (1 - cos (x)) = (1 - cos (x))^{2}

调整左侧

(1 - cos (x)) (1 - cos (x))

化简

(1 - cos (x)) (1 - cos (x)) : (1 - cos (x))^{2}

(1 - cos (x)) (1 - cos (x))

使用指数法则:

a^{b} \cdot a^{c} = a^{b + c}

(1 - cos (x)) (1 - cos (x)) = (1 - cos (x))^{1 + 1}

= (1 - cos (x))^{1 + 1}

数字相加:

1 + 1 = 2

= (1 - cos (x))^{2}

= (1 - cos (x))^{2}

= (1 - cos (x))^{2}

我们已展示，在两侧可以有相同的形式

\Rightarrow 真

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