已知tan^2A=2tan^B+1,求证sin^2B=2sin^2A-1_数学解答

已知tan^2A=2tan^B+1,求证sin^2B=2sin^2A-1

人气：478 ℃　时间：2020-01-29 20:21:40

解答

即sin²a/cos²a=2sin²b/cos²b+1sin²acos²b=2sin²bcos²a+cos²acos²bsin²a(1-sin²b)=2sin²b(1-sin²a)+(1-sin²a)(1-sin²b)sin²a...