Use trigonometric identities to simplify

Step-by-step explanation:

I am using trig identities and the formula for the difference of the cos of 2 angles to solve this. I'll do the steps one at a time. It's super tricky. First I'm just going to work on simplifying the sec² part and then I'll introduce the sin²(x) - sin⁴(x) when I need it. Beginning with the identity for the difference of the cos of 2 angles, knowing that sec²(x) = :

and expand that using the formula for the difference:

and all of that simplifies down to

which simplifies further to

Now we'll bring in the other term. This is what we have now:

and distribute in to get:

which simplifies to

and that, finally, simplifies down to a simple

can i get the link to the assignment?

step-by-step explanation:

answer: the value of x is 7cm

step-by-step explanation: