Question

Bài 1:Tìm nghiệm

a)f(x)=3(x-1)-4

b)g(x)=2(x-1)+3(x+2)

c)h(x)=4x²+4x-1

d)k(x)=\(\dfrac{x-1}{2}\) +\(\dfrac{x-2}{3}\)+1

Bài2:tìm x, y, z

a) \(\dfrac{x}{2}\)=\(\dfrac{y}{3}\)=\(\dfrac{z}{-4}\) và x+y+z =-5

b)\(\dfrac{x}{3}\)=\(\dfrac{y}{2}\)=;\(\dfrac{y}{3}\)=\(\dfrac{z}{5}\) và x+y-2z=11

c)\(\dfrac{x+1}{2}\)=\(\dfrac{y-2}{3}\)=\(\dfrac{z+3}{4}\) và x+2y-z=-30

Answer 1

Bài 1:

a: =>3x-3-4=0

=>3x=7

hay x=7/3

b: =>2x-2+3x+6=0

=>5x+4=0

hay x=-4/5

c: =>\(4x^2+4x-1=0\)

hay \(x\in\left\{\dfrac{-1+\sqrt{2}}{2};\dfrac{-1-\sqrt{2}}{2}\right\}\)

d: \(\Leftrightarrow3x-3+2x-4+6=0\)

=>5x+1=0

hay x=-1/5