2x + 2x+4 = 272
Tìm x ∈ N , biết.
a) 3 x + 1 : 3 4 = 81
b) 3 x + 3 . 3 x + 1 = 729
c) 2 x + 3 . 2 x = 128
d) 23 + 3 x = 5 6 : 5 3
e) 2 x + 2 x + 4 = 272
Tìm x ∈ N, biết.
a, 3 x + 1 : 3 4 = 81
b, 3 x + 3 . 3 x + 1 = 729
c, 2 x + 3 . 2 x = 128
d, 23 + 3 x = 5 6 : 5 3
e, 2 x + 2 x + 4 = 272
a, 3 x + 1 : 3 4 = 81
3 x - 3 = 3 4
x – 3 = 4
x = 7
Vậy x = 7
b, 3 x + 3 . 3 x + 1 = 729
3 2 x + 4 = 3 6
2x + 4 = 6
x = 1
Vậy x = 1
c, 2 x + 3 . 2 x = 128
2 2 x + 3 = 2 7
2x + 3 = 7
x = 2
Vậy x = 2
d, 23 + 3 x = 5 6 : 5 3
23 + 3 x = 5 3
23 + 3x = 125
3x = 102
x = 34
Vậy x = 34
e, 2 x + 2 x + 4 = 272
2 x + 2 x . 2 4 = 272
2 x ( 1 + 2 4 ) = 272
2 x . 17 = 272
2 x = 16
2 x = 2 4
x = 4
Vậy x = 4
a)x^3+4x+x-6=0
b)2x^3+3x^2-9x-10=0
c)x^3-x-6=0
d)(x^2-4x)^2+(8x-4)=-15
e)x(x+1)(x-1)(x+2)=24
g)(x^2-3x+3)(x^2-2x+3)=2x^2
h)(x+1)^4 x (x+3)^4=272
a)x^3+5x-6=0
x^3-x+6x-6
x(x^2-1)+6(x-1)=0
(x-1)(x(x+1)+6)
(x-1)(x^2+x+6)=0
=>x-1 hoac x^2+x+6
TH1
x-1=0
x=1
TH2
x^2+x+6=0
(x^2+2.1/2 x +1/4)-1/4+6=0
(x+1/2)^2=-23/4
vi (x+1/2)^2 >/0
=>pt vo nghiem
=>nghiem cua pt la 1
Phân tích đa thức thành nhân tử
\(2x^4+3x^3-9x^2-3x+2 \)
\(x^4-3x^3-6x^2+3x+1\)
\(x^4-8x^2-x+12\)
\(x^4-x^3-10x^2+2x+4\)
\((x+2)^4+(x+8)^4-272\)
\((3-x)^4+(4x-x)^4-(7-2x)^4\)
\(2x^4-x^3y+3x^2y^2-xy^3+2x^4\)
a) Ta có: \(2x^4+3x^3-9x^2-3x+2\)
\(=2x^4-2x^3-2x^2+5x^3-5x^2-5x-2x^2+2x+2\)
\(=2x^2\left(x^2-x-1\right)+5x\left(x^2-x-1\right)-2\left(x^2-x-1\right)\)
\(=\left(x^2-x-1\right)\left(2x^2+5x-2\right)\)
câu 3 tìm số tự nhiên x biết
1) (35 + x)-12=27
2) 2x - 5 =33 :32
\(\left(35+x\right)-12=27\\ 35+x=27+12=39\\ x=39-35=4\\ ---\\ 2x-5=3^3:3^2=3\\ 2x=3+5=8\\ x=\dfrac{8}{2}=4\)
1) (35 + x) -12 =27
=>35 + x = 39 => x = 4
2) 2x -5 = 33 : 32
=> 2x -5 =31 => 2x = 8
=> x = 4
1)
a) 12:{390:[5.10 mu2-(5 mu3+7 mu2.x)]}=4
b) 3+2 mux-1=24-[4 mu2-(2 mu2-1)
c) (2x-6)mu2016=(2x-6)mu16
d) (x+1)+(x+2)+(x+3)+...+(x+30)=795
e) 2 mu x+2 mu x+4=272
Ai là người giải nhanh mình tick cho.Nhưng phải trả lời trước thứ 5 đấy nhé!
bài 6:Tìm x, biết:A,1/4x-1/3=-5/9;B,3,5-Ix-1/2I=0,75;C,x-1/x-5=6/7;D,(x-4)mũ 2=25;E,2 mũ x+2 mũ x-4=272;F,(x+1/2)(2/3-2x)=0
Tìm x,biết:
1) (x2-6x)2 - 2(x-3)2=81
2) (x+3)4 + (x+5)4=16
3) (x+2)4 + (x+8)4=272
4) (2x2-3x+1)(2x2+5x+1)=9x2
5) (x+5)(x+6)(x+10)(x+12)=6006x2
Tìm x,biết:
1) (x2-6x)2 - 2(x-3)2=81
2) (x+3)4 + (x+5)4=16
3) (x+2)4 + (x+8)4=272
4) (2x2-3x+1)(2x2+5x+1)=9x2
5) (x+5)(x+6)(x+10)(x+12)=6006x2
Tìm x biết;
a) \(\frac{x-4}{2015}\)- \(\frac{1}{2015}\)= \(\frac{10-2x}{2015}\)
b) 2x + 2x+4 = 272
\(2^x+2^{x+4}=272\)
\(< =>2^x.\left(1+2^4\right)=272\)
\(< =>2^x.17=272\)
\(< =>2^x=272:17\)
\(< =>2^x=16\)
\(< =>2^x=2^4\)
\(=>x=4\)
a, x-4/2-15-1/2015=10-2x
qua điều trên:
Ta thấy rằng :
x-5=10-2x
=>
x=15-2x
=>
0=15-3x
=>x=5
Ta có:
2x+2x+4=272
=> 2x.(1+16)=272
=>2x.17=272
=>2x=16
=>x=4
\(\frac{x-4}{2015}-\frac{1}{2015}=\frac{10-2x}{2015}\)
\(< =>\frac{x-4-1}{2015}=\frac{10-2x}{2015}\)
\(< =>\frac{x-5}{2015}=\frac{10-2x}{2015}\)
\(< =>\frac{x-5}{2015}-\frac{10-2x}{2015}=0\)
\(< =>\frac{x-5-\left(10-2x\right)}{2015}=0\)
\(< =>\frac{x-5-10+2x}{2015}=0\)
\(< =>\frac{3x-15}{2015}=0\)
\(< =>3x-15=0\)
\(< =>3x=15\)
\(< =>x=5\)