Question

me ajudaaaa preciso com urgencia

Answer 1

$\sf sen {}^{2} (x) + cos {}^{2} (x) = 1 \\ \sf \left (\frac{ \sqrt{3} }{2} \right) {}^{2} + cos {}^{2} x = 1 \\ \sf \frac{3}{4} + cos {}^{2} x = 1 \\ \sf cos {}^{2} x = 1 - \frac{3}{4} \\ \sf cos {}^{2} x = \frac{4 - 3}{4} \\ \sf cos {}^{2} x = \frac{1}{4} \\ \sf cosx = \pm \sqrt{ \frac{1}{4} } \\ \sf cosx = \pm \frac{1}{2}$

$\boxed{ \sf cosx = \frac{1}{2} }$

$\sf sen(a + b) = sen(a).cos(b) + sen(b).cos(a)$

$\sf sen(x + x) = sen(x).cos(x) + sen(x).cos(x) \\ \sf sen(2x) = 2.sen(x).cos(x)$

$\sf sen(2x) = 2. \frac{ \sqrt{3} }{2} . \left( \frac{1}{2} \right) \\ \\ \sf sen(2x) = \sqrt{3} . \left( \frac{1}{2} \right) \\ \\ \boxed{\sf sen(2x) = \frac{ \sqrt{3} }{2} }$