Question

The value of $cose{c}^2{30}^{\circ }si{n}^2{45}^{\circ }-se{c}^2{60}^{\circ }$ is

• A. 1
• B. 2
• C. -2
• D. $2$

Answer 1

Answer: (B), (C)

The correct options are
B 2
C -2

$cose{c}^2{30}^{\circ }si{n}^2{45}^{\circ }-se{c}^2{60}^{\circ }=(2{)}^2\times {\left(\frac{1}{\sqrt{2}}\right)}^2-(2{)}^2=-2$