Question

化简根号下1-sin(3-π)cos(3-π)

详细过程 讲解下。打错了是
化简根号下1-2sin(3-π)cos(3-π)

Answer 1

1-2sin(3-π)cos(3-π)
=(sin(3-π))^2+(cos(3-π))^2-2sin(3-π)cos(3-π)
=(sin(3-π)-cos(3-π))^2
π/2<3<π
sin(3-π)=-sin3<0
cos(3-π)=-cos3>0
根号下1-2sin(3-π)cos(3-π)=cos(3-π)-sin(3-π)