单项选择题
A.ans=0.7854B.ans=0.78539816339745C.ans=7.8540e-001D.ans=7.853981633974483e-001
A.x=-2*pi:0.1:2*pi;plot(x,sin(x))B.x=-2*π:0.1:2*π;plot(x,sin(x))C.x=-2*pi:2*pi;plot(x,sinx)D.x=-2*3.1416:0.1:2*3.1416;plot(x,sinx)
A.pinv(A)B.inv(A)C.exp(A)D.expm(A)