证明 1/(sin(x)+1)+1/(csc(+1))=1

解答

证明

\frac{1}{sin ( x ) + 1} + \frac{1}{csc ( + 1 )} = 1

假

求解步骤

\frac{1}{sin ( x ) + 1} + \frac{1}{csc ( 1 )} = 1

两侧不相等

对于

\frac{1}{sin ( x ) + 1} + \frac{1}{csc ( 1 )} = 1

代入

x = 0

\frac{1}{sin ( 0 ) + 1} + \frac{1}{csc ( 1 )} = 1.84147 \dots

\frac{1}{sin ( 0 ) + 1} + \frac{1}{csc ( 1 )}

整理为小数形式

= 1.84147 \dots

两侧不相等

\Rightarrow 假

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