Найдите значение выражения:-7sin76градусов/сos38град*cos52град

[latex]-\frac{7\sin(76^\circ)}{\cos(38^\circ)\cos(52^\circ)} =\\\\= -\frac{7\sin(2*38^\circ)}{\cos(38^\circ)\cos(90^\circ - 38^\circ)} =\\\\= -\frac{7(2\sin(38^\circ)\cos(38^\circ))}{\cos(38^\circ)\sin(38^{\circ})} = \boxed{-14}\\\\ \left[ \ \sin(2a) = 2\sin(a)\cos(a); \ \cos(90^\circ - a) = \sin(a) \ \right][/latex]