Question

evaluate :1-cot² 45⁰ /1+sin² 90⁰

Answer 1

$$\begin{gathered} \mathrm{As}\mathrm{we}\mathrm{know}\mathrm{that}, \\ \sin 90=1\mathrm{and}\cot 45=1 \\ \mathrm{So}\mathrm{putting}\mathrm{these}\mathrm{value}\mathrm{in}, \\ \frac{1-{\cot }^{2}45}{1+{\sin }^{2}90}=\frac{1-1^2}{1+1^2} \\ =\frac{1-1}{1+1} \\ =\frac{0}{2} \\ =0 \end{gathered}$$