【非常着急】计算:tan^2+cot^2-(sin^2*tan^2+cos^2*cot^2)

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【非常着急】计算:tan^2+cot^2-(sin^2*tan^2+cos^2*cot^2)

【非常着急】计算:tan^2+cot^2-(sin^2*tan^2+cos^2*cot^2)
【非常着急】计算:tan^2+cot^2-(sin^2*tan^2+cos^2*cot^2)

【非常着急】计算:tan^2+cot^2-(sin^2*tan^2+cos^2*cot^2)
tan^2x+cot^2x-(sin^2x*tan^2x+cos^2x*cot^2x)
=tan^2x+cot^2x-sin^2x*tan^2x-cos^2x*cot^2x
=tan^2x(1-sin^2x)+cot^2x(1-cos^2x)
=tan^2x*cos^2x+cot^2x*sin^2x
=sin^2x+cos^2x
=1

tan^2+cot^2-(sin^2*tan^2+cos^2*cot^2)=tan^2-sin^2*tan^2+cot^2-cos^2*cot^2
=tan^2*cos^2+cot^2*sin^2
=sin^2+cos^2=1

你的函数没有自变量啊,难道都是相同的?如果是这样,那就切化弦,然后运算(最后化同名)

tan^2a+cot^2a-(sin^2a*tan^2a+cos^2a*cot^2a)
=tan^2a(1-sin^2a)+cot^2a(1-cos^2a)
=tan^2a*cos^2a+cot^2a*sin^2a
=sin^2a+cos^2a
=1