Tim x thuoc N biet
(7x-11)3=25.52 +200. ;b)3x+25=26.22+2.30.
2x+3.2=64 ;5x+1+5x=750
x15=x ;(x-5)4=(x-5)6
Tìm x ∈ N biết:
a) 2 x - 15 = 17
b) ( 7 x - 11 ) 3 = 2 5 . 5 2 + 200
tim x thuoc N
(7x-11)3=25.22+200
(7x-11)3=25.22+200
(7x-11)3=25+2+200
(7x-11)3=27+200
(7x-11)3=128+200
(7x-11)3=328
xong hết bt
Tim x biet
(7x -11 )^3 = 2^5 x 2^2 +200
(7x - 11)3 = 25 * 22 + 200
= (7x - 11)3 = 128 + 200
= 7x - 113 = 328
= 7x - 1331 = 328
= 7x = 328 + 1331
= 7x = 1659
= x = 1659 : 7
= x = 237
Vậy x = 237
Tìm x ∈ N biết:
a, 2 x - 15 = 17
b, 7 x - 11 3 = 2 5 . 5 2 + 200
a, 2 x - 15 = 17
⇒ 2 x = 2 = 2 2 ⇒ x = 1
b, 7 x - 11 3 = 2 5 . 5 2 + 200
⇒ 7 x - 11 3 = 1000 = 10 3
⇒ 7x – 11 =10
⇒ 7x = 21
⇒ x = 3
Tìm x ∈ N biết:
a) x - 1 2 = 36
b) 7 x - 11 3 = 2 5 . 5 2 + 200
c) x 11 = x
d) x 2 = 2 3 + 3 2 + 4 3
e) 2 . x 3 3 2 = 48
f) ( 2 x + 1 ) 3 = 125
22) tim x thuoc n biết
a)2^x=16
b)4^x=64
c)15^x=225
d)2^x-15=17
e)2^x-64=2^6
f)(7x-11)^3=2^5.5^2+200
a) \(2^x=16\)
\(2^x=2^4\)
\(\Rightarrow x=4\)
vay \(x=4\)
b) \(4^x=64\)
\(4^x=4^3\)
\(\Rightarrow x=3\)
vay \(x=3\)
c) \(15^x=225\)
\(15^x=15^2\)
\(\Rightarrow x=2\)
vay \(x=2\)
d) \(2^x-15=17\)
\(2^x=32\)
\(2^x=2^5\)
\(\Rightarrow x=5\)
vay \(x=5\)
e) \(2^x-64=2^6\)
\(2^x=2^6+64\)
\(2^x=128\)
\(2^x=2^7\)
\(\Rightarrow x=7\)
vay \(x=7\)
f) \(\left(7x-11\right)^3=2^5.5^2+200\)
\(\left(7x-11\right)^3=800+200\)
\(\left(7x-11\right)^3=1000\)
\(\left(7x-11\right)^3=10^3\)
\(\Rightarrow7x-11=10\)
\(\Rightarrow7x=21\)
\(\Rightarrow x=3\)
vay \(x=3\)
Có bao nhiêu số tự nhiên x thỏa mãn 7 x - 11 3 = 2 5 . 5 2 + 200 ?
A. 1
B. 2
C. 0
D. 3
Tìm x ∈ N biết:
a, x - 1 2 = 36
b, 7 x - 11 3 = 2 5 . 5 2 + 200
c, x 11 = x
d, x 2 = 2 3 + 3 2 + 4 3
e, 2 x 3 3 2 = 48
f, 2 x + 1 3 = 125
a, x - 1 2 = 36
ó x - 1 2 = 6 2
ó x – 1 = 6
ó x = 7
Vậy x = 7
b, 7 x - 11 3 = 2 5 . 5 2 + 200
=> 7 x - 11 3 = 800 + 200
=> 7 x - 11 3 = 1000
=> 7 x - 11 3 = 10 3
=> 7x – 11 = 10
=> 7x = 21
=> x = 3
Vậy x = 3
c, x 11 = x
=> x 11 - x = 0
=> x ( x 10 - 1 ) = 0
=>
d, x 2 = 2 3 + 3 2 + 4 3
=> x 2 = 81
=> x = 9
e, 2 x 3 3 2 = 48
=> 2 x 3 9 = 48
=> 2 x 3 = 48 . 9
=> x 3 = 216
=> x 3 = 6 3
=> x = 6
f, 2 x + 1 3 = 125
=> 2 x + 1 3 = 5 3
=> 2x + 1 = 5
=> 2x = 4
=> x = 2
tim x thuoc N , biet
x-20/11.13- 20/13.15-20/15.17...-20/53.55 =3/11