Question

[MR CROW]

tìm x:

a) \(\left(2x+5\right)\left(4x-10\right)+4x.\left(3-2x\right)^2=0\)

b) \(\left(2x-3\right)^2-\left(3x+1\right)^2=0\)

Answer 1

[Nguyễn Lê Phước Thịnh]

a: =>8x^2-20x+20x-50+4x(4x^2-12x+9)=0

=>8x^2-50+8x^3-48x^2+36x=0

=>8x^3-40x^2+36x-50=0

=>\(x\simeq4,29\)

b: =>(2x-3-3x-1)(2x-3+3x+1)=0

=>(-x-4)(5x-2)=0

=>x=2/5 hoặc x=-4