来自田广志的问题
高一三角函数化简求值[sin(7π/2+a)*cos(a-π)*sin^2(a+2π)]/[cos(3/2+π)*tan(π+a)*cos^3(-a-π)]
高一三角函数化简求值
[sin(7π/2+a)*cos(a-π)*sin^2(a+2π)]/[cos(3/2+π)*tan(π+a)*cos^3(-a-π)]
1回答
2020-08-04 16:36
高一三角函数化简求值[sin(7π/2+a)*cos(a-π)*sin^2(a+2π)]/[cos(3/2+π)*tan(π+a)*cos^3(-a-π)]
高一三角函数化简求值
[sin(7π/2+a)*cos(a-π)*sin^2(a+2π)]/[cos(3/2+π)*tan(π+a)*cos^3(-a-π)]
[sin(7π/2+a)*cos(a-π)*sin^2(a+2π)]/[cos(3π/2+a)*tan(π+a)*cos^3(-a-π)]
=[-cosa*(-cosa)*sin^2a]/[sina*tana*(-cos^3a)]
=cos^2asin^2a/sin^2a(-cos^2a)
=-1