I. cos300°+sin210°-tg135°=cos(360°-60°)+sin(180°+30°)-tg(180°-45°)=cos60°-sin30°+tg45°=sin30°-sin30°+1=1
IV. 200°=180°+20°=π+π/9=10π/9
Решить уравнение (sinx - 1/2) (cosx +1)= 0
x=<span>π(2n-1)</span><span>≈ 3.1416(20000n-10000</span>
x=2πn+<span>π≈ 62832n+3.1416
</span>x=<span>π(2n+1/6</span>)<span>≈</span>31416(20000n+0.16667)