Question

Calculați, folosind formule de calcul cât mai simple: a) (x+5)la a doua, b) (3x+7) la a doua, c) (3,2+5x) la a doua, d) (2x-3) la a doua, e) (5x-4) la a doua, f) (2,5x-8) la a doua, g) (x-3)(x+3), h) ( radical din 2x -radical din 3)(radical din 2x+ radical din 3) Sa știti ca x inseamna x, nu imultire, doar litera x DAU COROANAA

Answer 1

a) (x+5)²=x²+2·x·5+5²=x²+10x+25
b) (3x+7)²=(3x)²+2·x·7+7²=9x²+14x+49
c) (3,2+5x)²=3,2²+2·3,2·5x+(5x)²=10,24+32x+25x²
d) (2x-3)²=(2x)²-2·2x·3+3²=4x²-12x+9
e) (5x-4)²=(5x)²-2·5x·4+4²=25x²-40x+16
f)(2,5x-8)²= (2,5x)²-2·2,5x·8+8²=6,25x²-40x+64
g) (x-3) (x+3)= x²-3²=x²-9
h) (√2x-√3) (√2x+√3)= (√2x)²-(√3)²= 2x²-3