a) 5x(x-2)-x(5x-2)2= d) (x-3)(x+3)-(x-2)²≤19=

a)5x(x-2)-x(5x-2)2 = (5x²-10x)(5x²+2x)2 = (5x²-10x)(10x²+4x) = 50x⁴+20x³-100x³-40x² = 50x⁴+80x³-40x² d)(x-3)(x+3)-(x-2)²≤19 x²-9-(x²-4x+4)≤19 x²-9-x²+4x-4≤19 -13+4x≤19 |+13 4x≤32 |:4 x≤8

a) 5x(x-2) - x(5 -2)² = 5x² - 10x -x(25x² -20x+4)= =5x² -10 x -25x³+20x² -4x= 25x³+25x² -14x b) (x-3)(x+3)-(x-2)²≤19 x² - 9-(x² - 4x+4)≤ 19 x² -9-x² + 4x - 4≤19 4x ≤19+13 4x≤32 //:4 x ≤ 8