Question

Buna :3 As avea nevoie de ajutorul vostru la 3 exercitii de matematica-algebra :)

1) Efectuati produsele:
a. (x-1)(x-2)=?
b. (x-3)(x+6)=?
c. (x+4)(x+5)=?
d. (2x+7)(x-2)=?
e. (1-2x)(3x+5)=?
f. (2x+3)(5x-4)=?
g. (2x+3b)(3a-b)=?
h. (4x+3y)(4x-3y)=?

2. Calculati:
a. -2xy(x+3y) + 4x(xy-y²)=?
b. 3x(2x-1) + (x+2)(x-5)=?
c. (x+4)(x-3) - (x-1)(x+6)=?
d. 5x(x-4) - (x-3)(5x+2)=?
e. (7x-1)(x-3) - 5(x+2)(x+4)=?

3. Efectuati calculele:
a. (2x-1)(x+3) - 2(x² + x +1)=?
b. (x-3)[2x-3(x-1)] + x(x+5)=?
c. (3x-7)[3(x+1) - 2(x+3)] - 2x(x+6)=?
d. (2x+5)[5(x+1) + 2(x-2)] - 4x(5x-4)=?
e. (x+5)[3x - 2(x+2)] - x(x+4)=?

Va multumesc mult!:3

Answer 1

1.a)a. (x-1)(x-2)=x^2-2x-x+2=x^2-3x+2
b. (x-3)(x+6)=x²+6x-3x-18=x²+3x+18
c. (x+4)(x+5)=x²+5x+4x+20=x²+9x+20
d. (2x+7)(x-2)=2x^2-4x+7x-14=2x²+3x+14
e. (1-2x)(3x+5)=3x+5-6x²-10x=6x²-7x+5
f. (2x+3)(5x-4)=10x²-8x+15x-12=10x²+7x-12
g. (2x+3b)(3a-b)=6ax-2bx+9ab-3b²
h. (4x+3y)(4x-3y)=16x²-9y²

2.a)a. -2xy(x+3y) + 4x(xy-y²)=-2x²y-6xy²+4x²y-4xy²=6x²y-10xy²
b. 3x(2x-1) + (x+2)(x-5)=6x²-3x+x²-5x+2x-10=7x²-6x-10
c. (x+4)(x-3) - (x-1)(x+6)=x²-3x+4x-12-x²-6x+x+6= -4x-6
d. 5x(x-4) - (x-3)(5x+2)=5x²-20x-5x²-2x+15x+6=-7x+6
e. (7x-1)(x-3) - 5(x+2)(x+4)=7x²-21x-x+3-5(x²+4x+2x+8)=7x²-20x+3-5x²-20x-10x-40=2x²-50x-37