Question

DE O VALOR DE 2SEN30º - 2COS120º: *

1 ponto

2

-2

0​

Answer 1

$\boxed{\begin{array}{l}\sf cos(120^\circ)=-cos(60^\circ)\\\sf 2sen(30^\circ)-2cos(120^\circ)\\\sf=2sen(30^\circ)+cos(60^\circ)\\\sf cos(60^\circ)=sen(30^\circ)\\\sf =2 sen(30^\circ)+2sen(30^\circ)\\\sf=4sen(30^\circ)=4\cdot\dfrac{1}{2}=2\end{array}}$