Answer: The required simplified form is [tex]4\cos^2\theta.[/tex]
Step-by-step explanation: We are given to simplify the following trigonometric expression :
[tex]T=(\cos \theta-\cos\theta)^2+(\cos \theta+\cos \theta)^2.[/tex]
To simplify, first we need to evaluate the terms within the brackets.
The simplification is as follows :
[tex]T\\\\=(\cos \theta-\cos\theta)^2+(\cos \theta+\cos \theta)^2\\\\=0^2+(2\cos\theta)^2\\\\=0+4\cos^2\theta\\\\=4\cos^2\theta.[/tex]
Thus, the required simplified form is [tex]4\cos^2\theta.[/tex]
