tìm x biết:
2^x + 2^x + 4= 272
Tìm x biết :2x+2x+4=272
2x + 2x +4 = 272
(2 + 2)x + 4 = 272
4x + 4 = 272
4x = 272 - 4
4x = 268
Tìm X biết:
2x + 2x + 4 = 272
Tìm x thuộc Z biết:
2x+2x+4=272
tìm số tự nhiên x biết :2 mũ x công 2 mũ x công 4 =272
\(2^x+2^{x+4}=272\)
\(\Rightarrow2^x+2^x\cdot2^4=272\)
\(\Rightarrow2^x\left(1+2^4\right)=272\)
\(\Rightarrow2^x\cdot17=272\)
\(\Rightarrow2^x=272:17=16\)
\(\Rightarrow2^x=2^4\Rightarrow x=4\)
Tìm x, biết:
1/ √3 × x - 3 = √27
2/ √2 × x - √28 = √32
3/ √6 × x - 2√6 = √54
4/ √3 × x - √2 × x = √3 + √2
\(1,\sqrt{3}x-3=\sqrt{27}\)
\(\Leftrightarrow\sqrt{3}x-3=3\sqrt{3}\)
\(\Leftrightarrow\sqrt{3}\left(x-\sqrt{3}\right)=3\sqrt{3}\)
\(\Leftrightarrow x-\sqrt{3}=3\)
\(\Leftrightarrow x=3+\sqrt{3}\)
\(2,\sqrt{2}x-\sqrt{28}=\sqrt{32}\)
\(\Leftrightarrow\sqrt{2}x-2\sqrt{7}=4\sqrt{2}\)
\(\Leftrightarrow\sqrt{2}x=4\sqrt{2}+2\sqrt{7}\)
\(\Leftrightarrow x=\dfrac{\sqrt{2^2}\left(2\sqrt{2}+\sqrt{7}\right)}{\sqrt{2}}\)
\(\Leftrightarrow x=\sqrt{2}\left(2\sqrt{2}+\sqrt{7}\right)\)
\(\Leftrightarrow x=4+\sqrt{14}\)
\(3,\sqrt{6}x-2\sqrt{6}=\sqrt{54}\)
\(\Leftrightarrow\sqrt{6}\left(x-2\right)=3\sqrt{6}\)
\(\Leftrightarrow x-2=3\)
\(\Leftrightarrow x=5\)
\(4,\sqrt{3}x-\sqrt{2}x=\sqrt{3}+\sqrt{2}\)
\(\Leftrightarrow\left(\sqrt{3}-\sqrt{2}\right)x=\sqrt{3}+\sqrt{2}\)
\(\Leftrightarrow x=\dfrac{\sqrt{3}+\sqrt{2}}{\sqrt{3}-\sqrt{2}}\)
Tìm x biết \(2^x\)+ \(2^{x+4}\)=272
2x + 2x+4 = 272
=> 2x(1 + 24 ) = 272
=> 2x . 17 = 272
=> 2x = 272 : 17 = 16
=> 2x = 24
=> x = 4
=>2x+2x.24=272
=>2x.(1+24)=272
=>2x.17=272
=>2x=16
=>2x=24
=>x=4
Vậy x=4
L-i-k-e cho mình nha mình đang rất cần điểm
tìm số tự nhiên x biết rằng
a/5.3 mũ x =405
b/(x-2) mũ 5 =243
c/ 2 mũ x+2 mũ x+4=272
d/ (x+1)+(x+2)+......+(x+30)=795
a) \(5.3^x=405\)
\(\Rightarrow3^x=405:5\)
\(\Rightarrow3^x=81=3^4\)
\(\Rightarrow x=4\)
b) \(\left(x-2\right)^5=243\)
\(\Rightarrow\left(x-2\right)^5=3^5\)
\(\Rightarrow x-2=3\)
\(\Rightarrow x=5\)
c) \(2^x+2^{x+4}=272\)
\(\Rightarrow2^x.\left(1+2^4\right)=272\)
\(\Rightarrow2^x.17=272\)
\(\Rightarrow2^x=272:17=16\)
\(\Rightarrow2^x=2^4\)
\(\Rightarrow x=4\)
d) Từ x + 1 đến x + 2 có số số hạng là: (30 - 1) : 1 + 1 = 30 (số)
\(\left(x+1\right)+\left(x+2\right)+...+\left(x+30\right)=795\)
\(\Rightarrow30x+\frac{\left(30+1\right).30}{2}=795\)
\(\Rightarrow30x+465=795\)
\(\Rightarrow30x=330\)
\(\Rightarrow x=330:30\)
\(\Rightarrow x=11\)
a) \(5.3^x=405\)
\(3^x=\frac{405}{5}=81\)
\(3^x=3^4\)
Vậy x = 4
b ) \(\left(x-2\right)^5=243\)
\(\left(x-2\right)^5=3^5\)
\(\Rightarrow x-2=3\)
\(\Rightarrow x=3+2=5\)
Vậy x = 5
a, 5.3 x =405
3x=405:5
3x=81
=> x=4
b, (x-2)5=243
(x-2)5=35
vì 5=5
nên x -2=3
<=> x=3+2
=>x=5
c, 2x + 2x+4 = 272
2x+2x+24=272
2x(1+24)=272
2x.17=272
2x=272:17
2x=16
vì 16=24
=>x=4
d, (x+1)+(x+2)+(x+3)+.....+(x+30)=795
(x+x+x+..+x)+(1+2+3+..+30)=795
30x+456=795
30x=795-456
30x=330
x=330:30
x=11
vậy x=11
hc tốt
Tim x biết :2x+2x+4=272
2x + 2x + 4 = 272
=> 2x + 2x . 24 = 272
=> 2x .( 1 + 24 ) = 272
=> 2x . 17 = 272
=> 2x = 272 : 17 = 16
=> 2x = 24
=> x = 4
Vậy x = 4
tách số thứ 2 thành 2 ^ x . 2^ 4 có chung nhe làm bình thường nha
\(2^x+2^{x+4}=272\)
\(2^x+2^x\cdot2^4=272\)
\(2^x\left(1+16\right)=272\)
\(2^x\cdot17=272\)
\(2^x=272:17\)
\(2^x=16\)
\(\Rightarrow x=4\)
Tìm x
2x+2x+4=272
2x+2x+4=272
=> 2x.(1+24)=272
=> 2x.(1+16)=272
=> 2x.17=272
=> 2x=272:17
=> 2x=16
=> 2x=24
=> x=4