Given: ( cos 0°+sin 45°+sin 30° ) ( sin 90° - cos 45° + cos 60° )
To find: The value of the above.
Solution: Use the formulas:
sin 30 = \(\frac{1}2\), sin 45 = \(\frac{1}{\sqrt2}\), cos 60 = \(\frac{1}2\)
Solve,( cos 0°+sin 45°+sin 30°) ( sin 90° - cos 45° + cos 60°)
Use the identity: (a - b)(a + b) = a2 - b2
= \(\frac{14}8\)
= \(\frac{7}2\)