Question

utilizati formulele de calcul prescurtat in exercitiile urmatoare
a) (x+2)² + (x - 3)² - (x+1)(x-1)
b) (2x+ 1)² - (x+6)(x-6)-3(x-2)²
c) (x-5)² - (x-4)(x+4) +(x+1)²
d) (3x-2)² -5(x-3)(x+3)-(2x+3)²
va rog dau coroana

Answer 1

a) (x+2)² + (x - 3)² - (x+1)(x-1) =
=x²+4x+4+x²-6x+9-x²+1=
=x²-2x+14

b) (2x+ 1)² - (x+6)(x-6)-3(x-2)² =
=4x²+4x+1-x²+36-3(x²-4x+4)=
=4x²+4x+1-x²+36-3x²+12x-12=
=16x+25

c) (x-5)² - (x-4)(x+4) +(x+1)²=
=x²-10x+25-x²+16+x²+2x+1=
=x²-8x+42

d) (3x-2)² -5(x-3)(x+3)-(2x+3)² =
=9x²-12x+4-5x²+45-4x²-12x-9=
=-24x+40