xx−1. yx2+3xy+9y2. x+1x−5. x+1x−2. a+b+ca. x+5x+3. x+1x+3. [2]Exercise43. a+b+2a−b. a−b−2a+b. a−1+2aa2−a−1. 2x−4+5x+1. 4 x 2 − 2 x +