Question

The value of the expressions
$({\sin }^2{30}^o+{\cos }^2{30}^o)-({\sin }^2{60}^o+{\cos }^2{60}^o)+({\sin }^2{45}^o+{\cos }^2{45}^o)$=

• A. $0.25$
• B. $0.5$
• C. $0.75$
• D. $1$

Answer 1

The correct option is D $1$

We know, ${\sin }^2\theta +{\cos }^2\theta =1$

Therefore, the value of

$({\sin }^2{30}^o+{\cos }^2{30}^o)-({\sin }^2{60}^o+{\cos }^2{60}^o)+({\sin }^2{45}^o+{\cos }^2{45}^o)$ is

$=1-1+1$

$=1$