Question

Efectuati.
a) (2x+1)³+(x+2)³+(x-2)(x+2)
b) (x-1)³+(2-x)³-(x+3)²
c) (x-3y)³+(y+2)³+(x+y-2)²
d) (x-2y+2)²+(x+1)³-(y+2)²
e) (4-3x)²-(3x-4)²+(3x-4)³
f) (x+2y)³+(x+2y)²-(x+2y+1)²

Answer 1

(a+b)(a-b) = a^2 - b^2
(a+b)^2 = a^2 + b^2 + 2ab
(a + b)^3 = a^3 + b^3 + 3ab(a + b)

a) (2x+1)³+(x+2)³+(x-2)(x+2)
8x^3+12x^2+6x+1+x^3+6x^2+12x+8+x^2+2x−2x−4
9x^3+19x^2+18x+5

b) (x-1)³+(2-x)³-(x+3)²
x^3−3x^2+3x−1−x^3+6x^2−12x+8−x^2−6x−9
2x^2−15x−2

c) (x-3y)³+(y+2)³+(x+y-2)²
x^3−9x^2y+27xy^2−27y^3+y^3+6y^2+12y+8+x^2+2xy+y^2−4x−4y+4
x^3−9x^2y+27xy^2−26y^3+x^2+2xy+7y^2−4x+8y+12

d) (x-2y+2)²+(x+1)³-(y+2)²
x^2−4xy+4y^2+4x−8y+4+x^3+3x^2+3x+1−y^2−4y−4
x^3+4x^2−4xy+3y^2+7x−12y+1

e) (4-3x)²-(3x-4)²+(3x-4)³
9x^2−24x+16−9x^2+24x−16+27x^3−108x^2+144x−64
27x^3−108x^2+144x−64

f) (x+2y)³+(x+2y)²-(x+2y+1)²
x^3+6x^2y+12xy^2+8y^3+x^2+4xy+4y^2−x^2−4xy−4y^2−2x−4y−1
x^3+6x^2y+12xy^2+8y^3−2x−4y−1