D = (2x+3)²+(2x+3)(7x-2)
1) D = 4x²+12x+9+14x²-4x+21x-6
= 18x²+29x+3
2) D =(2x+3)(2x+3)+(2x+3)(7x-2)
= (2x+3)[(2x+3)+(7x-2)]
= (2x+3)(9x+1)
si x=4, D = (2*4+3)(9*4+1)
= 11 * 37
= 407
E = 16 - (2x+3)²
si x=-1, E = 16 - (2*(-1)+3)² = 16 - 1 = 15
E = 16 - (2x+3)² = 16 - (4x²+12x+9)
= -4x² - 12x + 7