Answer:
13
Step-by-step explanation:
We have the following expression:

By combining similar terms, we get

now, 2 times 3 is 6 and to add exponents, both the exponents and variables should be alike:

Similarly,

Therefore, the answer is

we can divide the equation on (x+1) and if we have a real solutons (x+1) is a factor
is a factor because the remainder is 0
so the new form of the equation is
Factor out cosx: cosx(sinx-2)=0
cosx=0 or sinx-2=0
cosx=0 or sinx=2
the largest value of sinx is 1, sinx will never be 2, so cosx=0, x=π/2 or 3π/2 are the two answers.