HOC24
Lớp học
Môn học
Chủ đề / Chương
Bài học
<=>(3x-1)(x2+2-7x+10)=0
<=>(3x-1)(x2-7x+12)=0
<=>(3x-1)(x-4)(x-3)=0
<=>3x-1=0 hay x-4=0 hay x-3=0
<=> 3x=1 x=4 x=3
<=> x=1/3
S=(1/3;4;3)
a) 2x3+6x2 = x2 + 3x
<=> 2x2(x+3) = x(x+3)
<=> 2x2(x+3) - x(x+3)=0
<=>(x+3)(2x2-x)=0
<=>(3+x)x(2x-1)=0
<=> x=0 hay x+3=0 hay 2x-1=0
x=-3 x=1/2
x=1/2
S=(-3;1/2)
b)(3x-1)(x2+2) = (3x-1)(7x-10)
<=>(3x-1)(x2+2)-(3x-1)(7x-10)=0
<=> (3x-1)(x2-2-7x+10)=0
<=> (3x-1)(x2-7x+12)=0
<=> (3x-1)(x-3)(x-4)=0
<=> 3x-1= 0 hay x-3=0 hay x-4=0
<=> 3x=1 x=3 x=4
S=(1/3;3;4)