Question

1) Descompune in factori : V a rog ajutati-ma !!!! Daca se poate si cu niste explicatii ca nu am inteles deloc lectia

a) 15a -5b

b) 18x - 48y

c) 9x² -3xy

d) 2x³-4x²+8x

e ) 12xy³-18x²y²+36x³y2

f') ( x-1 ) ( x+5) ( x-1 ) (2x-5)

Answer 1

) 15a -5b=5(3a-b)

b) 18x - 48y =6(3x-8y)


c) 9x² -3xy=3x(3x-y)

d) 2x³-4x²+8x=2x(x²-2x+4)=2x(x-2)²


e ) 12xy³-18x²y²+36x³y2=6xy²(2y-3x+3x²)


f') ( x-1 ) ( x+5)+ ( x-1 ) (2x-5) =(x-1)(x+5+2x-5)=30(x-1)
sau daca este cu -

( x-1 ) ( x+5)- ( x-1 ) (2x-5) =(x-1)(x+5-2x+5)=(x+1)(10-x)