Without actual division prove that X4+2X3+2X2+2X-3 is exactly divisible by X2+2X-3.
Proof.
Factorize the polynomial X4+2X3+2X2+2X-3 .
X4+2X3+2X2+2X-3=X4+2X3-3X2+X2+2X-3=X2X2+2X-3+1X2+2X-3=X2+1X2+2X-3
Since, X2+2X-3 is a factor of X4+2X3+2X2+2X-3 .
Hence, X4+2X3+2X2+2X-3 is exactly divisible by X2+2X-3.