ABCD is a rectangle of which AC is a diagonal. The value of (tan2 ∠CAD + 1)sin2 ∠BAC is?

Answer: Option C

= (tan²α + 1 )sin²β
= (tan²45° + 1 )sin²45°
$$=(1+1){\left(\frac{1}{\sqrt{2}}\right)}^2$$
$$=2\times \frac{1}{2}=1$$