Question

giúp tui câu b;d;f bài 2 zớiiii :((

Answer 1

Bài 2: 

a: \(\Leftrightarrow\left(x-1\right)\left(3x+1\right)=0\)

=>x=1 hoặc x=-1/3

b: \(\Leftrightarrow\left(2x-5\right)\left(2x+5-2x-7\right)=0\)

=>2x-5=0

=>x=5/2

c: \(\Leftrightarrow\left(x-3\right)\left(x^2-4\right)=0\)

=>(x-3)(x-2)(x+2)=0

hay \(x\in\left\{3;2;-2\right\}\)

d: =>\(-4x^2-15x+4x^2-25=0\)

=>-15x=25

=>x=-5/3

e: =>\(\left(2x-5\right)\left(2x+5-2x-7\right)=0\)

=>2x-5=0

=>x=5/2

f: =>\(\left(x+2\right)\left(x^2-2x+4+x-9\right)=0\)

=>(x+2)(x^2-x-5)=0

hay \(x\in\left\{-2;\dfrac{1+\sqrt{21}}{2};\dfrac{1-\sqrt{21}}{2}\right\}\)