cos7π/3-sin^2(17π/4)-1/3tan^2(π/3)sin3π/2+cos0=?

cos7π/3-sin^2(17π/4)-1/3tan^2(π/3)sin3π/2+cos0=?
cos7π/3-sin^2(17π/4)-1/3tan^2(π/3)sin3π/2+cos0=?

cos7π/3-sin^2(17π/4)-1/3tan^2(π/3)sin3π/2+cos0=?
cos(7π/3)-sin^2(17π/4)-1/3tan^2(π/3)sin(3π/2)+cos0
=cos(π/3)-sin^2(π/4)-1/3tan^2(π/3)sin(3π/2)+cos0
=1/2-(√2/2)^2-(1/3)*(√3)^2*(-1)+1
=1/2-1/2+1+1
=2
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