 Hello and welcome to the session. In this session we are going to discuss the following question and the question says that, simplify the following rational expression and the expression given is x raised to the power 4 minus 1 whole upon x squared plus 1 the whole into x plus 1 the whole. We know that to simplify our rational expression first we factorize both numerator and denominator completely and then we reduce the expression by cancelling common factors. With this key idea we shall proceed to the solution. Here we are given a rational expression x raised to the power 4 minus 1 whole upon x squared plus 1 the whole into x plus 1 the whole. We have to simplify it. From the key idea we know that to simplify our rational expression we first factorize both numerator and denominator completely. Now the given expression can be written as x squared whole squared minus 1 squared whole upon x squared plus 1 the whole into x plus 1 the whole. Now we know that a squared minus b squared is equal to a plus b the whole into a minus b the whole. So using the same formula here we get x squared plus 1 the whole into x squared minus 1 the whole whole upon x squared plus 1 the whole into x plus 1 the whole. Now again we can rewrite this expression as x squared plus 1 the whole into x squared minus 1 squared the whole whole upon x squared plus 1 the whole into x plus 1 the whole and this is equal to x squared plus 1 the whole. Now using the same formula again here we get x plus 1 the whole into x minus 1 the whole whole upon x squared plus 1 the whole into x plus 1 the whole and now in the second step we reduce the expression by cancelling common factors. Now here the common factors are x squared plus 1 the whole into x plus 1 the whole so we cancel out the common factors and we get x minus 1. So on simplifying the given expression we get x raised to the power 4 minus 1 whole upon x squared plus 1 the whole into x plus 1 the whole is equal to x minus 1. This is the required answer. This completes our session. Hope you enjoyed this session.