Question

Find the value of $\sin {35}^{\circ }\cos {55}^{\circ }+\cos {35}^{\circ }\sin {55}^{\circ }$

Answer 1

$sin{35}^{0}cos{55}^0+cos{35}^{0}sin{55}^0=sin{35}^{0}cos({90}^0-{35}^0)+cos{35}^{0}sin({90}^0-{35}^0)$
$=sin{35}^{0}sin{35}^0+cos{35}^{0}cos{35}^0$
$=si{n}^2{35}^0+co{s}^2{35}^0$
$=1$