Question

比较大小(1)sin(-π/16)与sin(-π/5) (2)cos(-33/5π)与cos(-13/3π)

Answer 1

(1) sin(-π/16)=-sin(π/16)

sin(-π/5)=-sin(π/5)

sin(π/16)-sin(π/5)

sin(-π/16)>sin(-π/5)

(2)cos(-33/5π)=cos(-7π+2/5π)=-cos(2/5π)

cos(-13/3π)=cos(-4π-1/3π)=cos(1/3π)

-cos(2/5π)