化简sin(A+π/4)sin(A-π/4)/sin^4A-cos^4A

来源：学生作业帮编辑：拍题作业网作业帮分类：数学作业时间：2024/05/21 06:54:08

原式=cos[π/2-(A+π/4)]sin(A-π/4)/(sin²A+cos²A)(sin²A-cos²A)
=cos(π/4-A)sin(A-π/4)/1×(sin²A-cos²A)
=cos(A-π/4)sin(A-π/4)/1×(sin²A-cos²A)
=[1/2sin2(A-π/4)]/cos2A
=[1/2sin(2A-π/2)]/cos2A
=[-1/2cos2A]/cos2A
=-1/2

sin(π/4-a) cos（a-π/4）化简 1-sin^6a-cos^6a分之1-sin^4a-cos^4a 化简化简1-sin^4a-cos^4a/1-sin^6a-cos^6a (1-sin^6a-cos^6a)/(sin^2a-sin^4a) (cos a)^4+(sin a)^2*(sin a)^2+(sin a)^2=? 化简 sin^4a-cos^4b 化简:sin(-a)cos(2π+a)sin(-a-π) sin(a-π/4)+cos(a+π/4)怎么解? 已知a属于（0,π/2）,且2sin^2 a-sin a cos a-3cos^2 a=0,求SIN(a+兀/4)/SI 求值:1-sin^6a-cos^6a/1-sin^4a-cos^4a (1-sin^4a-cos^4a)/(1-sin^6a-cos^6a) （1-sin^6a-cos^6a)/(1-sin^4a-cos^4a)=?