\(\left(x-3\right)\left(x+x^2\right)+\left(x-5\right)\left(x+1\right)-x^3=12\)
\(\Leftrightarrow x^2+x^3-3x-3x^2+x^2+x-5x-5-x^3=12\)
\(\Leftrightarrow-x^2-7x-5=12\Leftrightarrow-x^2-7x-17=0\)
Ta có : \(\left(-7\right)^2-4\left(-17\right)\left(-1\right)< 0\)Vậy phương trình vô nghiệm
Tìm x biết:
a) 2x(3x+1) – (2x+3)(3x-2) = 12
b) (x+2)2 – (x-3)(x+3) = 5
Tìm x, biết :
a) (x-2)3 +6(x+1)2-x3+12=0
b) (x-5) (x+5) - (x+3)2+3(x-2)2=(x+1)2- (x+4)(x-4)+3x2
c) (2x+3)2 +(x-1)(x+1)=5(x+2)2-(x-5)(x+1)+(x+4)
d) (1-3x)2-(x-2)(9x+1)=(3x-4)(3x+4)-9(x+3)2
Giúp mk với ạ, mk cảm ơn !
tìm x ,biết
a, x^2 -4x =12
b, ( 5x+1)^2 - (5x -3)(5x+3)=30
c, (x-1) ( x^2 +x +1 ) + x(x +2) (2-x)=5
d, 5x(x-3)^2 -5 (x-1)^3 +15 (x+4) (x-4) =5
Tìm x biết
a) (x+2).(x+3) - (x-2).(x+5)=10
b) (3x+2). (2x+9) - (x+2). (8x+11)=(x+1).(3-2x)
c) 3.(2x-1).(3x-1)-(2x-3).(9x-1)=0
d) (5x-8).(4x-5)-(3x-4).(2x+12)=12
Tìm x biết
a/3x*(12*x-4)-9*x*(4x-3)=30
b/x*(5-2*x)+2*x*(x-1)=15
Tìm x. biết:
a/12(x-2)(x+2)-3(2x+3)2 =52
b/(2x+1)2 -4(x-1)(x+1)+2x=5
c/(x-2)3-(x-3)(x2+3x+9)+6(x+1)2=15
d/(x+2)(x2-2x+4)-x(x2+2)=15
e/ 12(x-2)(x+2)-3(2x+3)2=57
f/ (3-x)(3+x)+(3x-1)2+6x=522
g/(2x+1)2-4(x-1)(x+1)+2x=5
Tìm x biết: b/(x-2)^3+6(x+1)^2-x^3+12=0
Tìm x biết
(x−3)(x+x^2)+2(x−5)(x+1)−x^2=12.
tìm x
5x(x^3)x^2-5(x-1)^3+15(x-4)(x+4)=5
2)Cho A,B,Q là các đa thức
Biết A=2x^3-x^2+5x-12;B=2x-3
a)Tìm Q
b)C/Minh rằng Q>0 với mọi x
c)Tìm x để Q đạt gtnn
