Q. 9 - Precalculus Enhanced with Graphing Utilities

Question

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

Step-by-Step Solution

Answer

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

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 

$1-3 =-2$