A=27.18
There is a photo showing the answer and the formula and stuff hope this helps
Answer:
Step-by-step explanation:
cos 225 = -cos 45 = -1/√2.
sin 225 = -sin45 = -1√2.
I think it’s b not sure tho

If x²-1 is a factor of the polynomial, both x-1 and x+1 are factors of it.
According to the remainder theorem, if a binomial x-a is a factor of a polynomial p(x), then p(a)=0.
If x-1 and x+1 are factors of the polynomial p(x)=ax⁴+bx³+cx²+dx+e, then p(1)=0 and p(-1)=0.