Which of the following is true for all values of $\mathrm{\theta } (0^{\circ }\le \mathrm{\theta }\le {90}^{\circ })?$
 

Evaluate: $\frac{5}{{\cot }^{2 }30°}+\frac{1}{{\displaystyle {\sin }^2}{\displaystyle }{\displaystyle 60}{\displaystyle °}}-{\cot }^2 45°+2{\sin }^2 90°$

If $\mathrm{\theta }$ is an acute angle and $\sin \mathrm{\theta }=\cos \mathrm{\theta }$, find the value of ${\tan }^2\mathrm{\theta }+{\cot }^2\mathrm{\theta }-2$.

$({\sec }^{2 }\mathrm{\theta }-1)({\mathrm{cosec}}^{2 }\mathrm{\theta }-1)$ is equal to:

Evaluate: $2 {\sec }^2\mathrm{\theta }+3 {\mathrm{cosec}}^2\mathrm{\theta }-2 \mathrm{sin\theta } \mathrm{cos\theta }$ if $\mathrm{\theta }=45°$.

Evaluate: If $\sin \mathrm{\theta }-\cos \mathrm{\theta }=0,$ then find the value of ${\sin }^4 \mathrm{\theta }+{\cos }^4 \mathrm{\theta }$.