Question

Find the exact value of $\sin {\left(14°\right)}^2+\cos {\left(14°\right)}^2-3$

Short answer

The exact value of the given function is :$-2$

Step-by-step solution

Step 1. Given information

${\left(\sin \left(14°\right)\right)}^2+{\left(\cos \left(14°\right)\right)}^2-3$

We know about trigonometric properties, that

${\sin }^2\left(\varnothing \right)+{\cos }^2\left(\varnothing \right)=1$

Step 2. Using trigonometric properties  

${\left(\sin \left(14°\right)\right)}^2+{\left(\cos \left(14°\right)\right)}^2=1$

using this

$1-3=-2$