$\cos^2\left(a\right)+\sin^2\left(x\right)\cdot\cos\left(a\right)$

$-9+10+4+5+6$

$-x^0-y^0$

$\left(1-cos^2x\right)\left(1+cos^2x\right)2sin^2x-sin^4x\:$

$\left(1-3x\right)\left(1+12x+60x^2+160x^3+240x^4\right)$

$5\left(5\right)^3-7\left(5\right)^2\left(4\right)+4^3$

$0^0+1$