Answer:
No this is not the same as cos(2Ф)
Step-by-step explanation:
First I changed the [tex]cos^{2}[/tex]Ф into 1-[tex]sin^{2}[/tex]Ф
I then foiled the (1-2[tex]sin^{2}[/tex]Ф)(1-[tex]sin^{2}[/tex]Ф) and that resulted in 1-[tex]sin^{2}[/tex]Ф-2[tex]sin^{2}[/tex]Ф+2[tex]sin^{4}[/tex]Ф
From there, I then cancelled the two 2[tex]sin^{4}[/tex]Ф and combined like terms and was left with 1-3[tex]sin^{2}[/tex]Ф
Now 1-3[tex]sin^{2}[/tex]Ф ≠ cos(2Ф)
