Question

9. (2)( left(cos 0^{circ}+sin 45^{circ}+sin 30^{circ}right) )
( begin{aligned}=left(1+frac{1}{sqrt{2}}+frac{1}{2}right)left(1-frac{1}{sqrt{2}}+frac{1}{2}right) &left.=00^{circ}right) =left(frac{3}{2}+frac{1}{sqrt{2}}right)left(frac{3}{2}-frac{1}{sqrt{2}}right) =frac{9}{4}-frac{1}{2}=frac{9-2}{4}=frac{7}{4} end{aligned} )

# 9. (cos0° + sin 45° + sin 30°) (sin 90° - cos 45º + cos 60°) QT HA

Solution