计算:arctan(1-x)+arctan(1+x)的值
问题描述:
计算:arctan(1-x)+arctan(1+x)的值
答
tan(A+B) = (tanA+tanB)/(1-tanAtanB)
tan(arctan(1-x)+arctan(1+x))
= (1-x+1+x)/(1-(1-x)(1+x))
= 2/x^2
arctan(1-x)+arctan(1+x)
= arctan(2/x^2)