Question

Deschideti parantezele si reduceti termenii asemenea:
a) (x+4)*(1+x)
b) (3+y)*(2+y)
c) (x+2)*(3x+1)
d) (4+3x)*(1+x)
e) (m+5n)(5m+n)
f) (5x+3y)(2y+4x)
Dau maximul de puncte!

Answer 1

a) (x+4)*(1+x) = x+x²+4+4x = 5x+x²+4 = x²+5x+4
b) (3+y)*(2+y) = 6+3y+2y+y² =6+5y+y² = y²+5y+6
c)  (x+2)*(3x+1) = 3x²+x+6x+2 = 3x²+7x+2
d)  (4+3x)*(1+x) = 4+4x+3x+3x² = 4+7x+3x² = 3x²+7x+4
e)  (m+5n)(5m+n) = 5m²+mn+25mn+5n² = 5m²+26mn+5n²
f) (5x+3y)(2y+4x) = 10xy+20x²+6y²+12xy = 22xy+20x²+6y²

Answer 2

(x+4)*(1+x) = x+x^2+4+4x = x^2+5x+4
(3+y)*(2+y) = 6+3y+2y+y^2 = y^2+5y+6
(x+2)*(3x+1) = 3x^2+x+6x+2 = 3x^2+7x+2
(4+3x)*(1+x) = 4+4x+3x+3x^2 = 3x^2+7x+4
(m+5n)*(5m+n) = 5m^2+mn+25mn+5n^2 = 5m^2+5n^2+26mn
(5x+3y)*(2y+4x) = 10xy+20x^2+6y^2+12xy = 20x^2+22xy+6y^2