2.2+10=x
Tìm x
Tìm x biết x+x+1/2.2/5+x+8/10=136
Tìm x biết:
2.22+3.23+4.24+...+x.2x=2x+10
tìm số tự nhiên x, biết
a)80-(x-6)=3^2.2^3
b)495-5.(x+4)=10
a) <=>80-x+6=9.8
<=>86-x=72
<=>x=14
b) <=>495-5x-20=10
<=>475-5x=10
<=>5x=465
<=>x=93
1)Tìm x:
a.(15.x+2.23)-4=10
b.3.x.155=156
a) ( 15x +2.2\(^3\)) -4=10
\(\Rightarrow15x+2^4=14\)
\(\Rightarrow15x=14-16\)
\(\Rightarrow x=\left(-2\right):15\)
\(\Rightarrow x=-\frac{2}{15}\)
b)\(3x.15^5=15^6\)
\(\Rightarrow3x=15^6:15^5\)
\(\Rightarrow3x=15\)
\(\Rightarrow x=\frac{15}{3}=5\)
a) (15x+2.23)-4 = 10
15x+2.23 = 10+4
15x+2.23 = 14
=> 15x+24=14
15x+16=14
15x=14-16
15x = -2
x = -2:15
x = -2/15
b) 3x.155 = 156
3x = 156 : 155
3x = 151
x = 15 : 3
x = 5
a) <=> 15x + 16 - 4 = 10
<=> 15x = -2
<=> x = -2/15
b) <=> 3x = 15
<=> x = 5
Tìm x thuộc N sao cho:
2.2^23.2^3+............+n.2^n= 2^n+10
tìm x, biết x là số tự nhiên
b)2.3^x=162
c)(2x-15)^5=(2x-15)^3
d)3^(x+2) -5.3^x
e)7.4^(x-1)+4(x+1)=23
f)2.2^(2x)+4^3.4^x=1056
10 -{[(x:3+17):10+3.2^4]:10}=5
gấp, mọi ng giúp mình với
`#3107`
b)
`2.3^x = 162`
`\Rightarrow 3^x = 162 \div 2`
`\Rightarrow 3^x = 81`
`\Rightarrow 3^x = 3^4`
`\Rightarrow x = 4`
Vậy, `x = 4`
c)
`(2x - 15)^5 = (2 - 15)^3`
\(\Rightarrow \)`(2x - 15)^5 - (2x - 15)^3 = 0`
\(\Rightarrow \)`(2x - 15)^3 . [ (2x - 15)^2 - 1] = 0`
\(\Rightarrow\left[{}\begin{matrix}\left(2x-15\right)^3=0\\\left(2x-15\right)^2-1=0\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}2x-15=0\\\left(2x-15\right)^2=1\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}2x=15\\\left(2x-15\right)^2=\left(\pm1\right)^2\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{15}{2}\\2x-15=1\\2x-15=-1\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{15}{2}\\2x=16\\2x=-14\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=\dfrac{15}{2}\\x=8\\x=-7\end{matrix}\right.\)
Vậy, `x \in`\(\left\{-7;8;\dfrac{15}{2}\right\}.\)
`d)`
\(3^{x+2}-5.3^x=?\) Bạn ghi tiếp đề nhé!
`e)`
\(7\cdot4^{x-1}+4^{x-1}=23?\)
\(4^{x-1}\cdot\left(7+1\right)=23\\ \Rightarrow4^{x-1}\cdot8=23\\ \Rightarrow4^{x-1}=\dfrac{23}{8}\)
Bạn xem lại đề!
`f)`
\(2\cdot2^{2x}+4^3\cdot4^x=1056\)
\(\Rightarrow2\cdot2^{2x}+\left(2^2\right)^3\cdot\left(2^2\right)^x=1056\\ \Rightarrow2\cdot2^{2x}+2^6\cdot2^{2x}=1056\\ \Rightarrow2^{2x}\cdot\left(2+2^6\right)=1056\\ \Rightarrow2^{2x}\cdot66=1056\\ \Rightarrow2^{2x}=1056\div66\\ \Rightarrow2^{2x}=16\\ \Rightarrow2^{2x}=2^4\\ \Rightarrow2x=4\\ \Rightarrow x=2\)
Vậy, `x = 2`
_____
\(10 -{[(x \div 3+17) \div 10+3.2^4] \div 10}=5\)
\(\Rightarrow\left[\left(x\div3+17\right)\div10+48\right]\div10=10-5\)
\(\Rightarrow\left[\left(x\div3+17\right)\div10+48\right]\div10=5\)
\(\Rightarrow\left(x\div3+17\right)\div10+48=50\)
\(\Rightarrow\left(x\div3+17\right)\div10=2\)
\(\Rightarrow x\div3+17=20\)
\(\Rightarrow x\div3=3\\ \Rightarrow x=9\)
Vậy, `x = 9.`
Tìm x thuộc N biết:
2.2^2 + 3.2^3 + 4,2^4 +...+ x.2^x = 2x^10
Giúp mình với ạ
1.Tìm x biết:
(x-4)^2 = (x-4)^4
2. Tìm số n thuộc N biết
2.2^2+3.2^3+4.2^4+5.2^5+...+ n.2^n = 2^n+10
Giúp mình với
x+x+1/2.2/5+x+8/10=136
=> 3x + 1/5 = 136 - 8/10
=> 3x + 1/5 = 125,2
=> 3x = 125
=> x = 125/3
tick đúng cho mình néh !
vậy cậu giải luôn hộ tớ cái bài lúc này nhé !
Tìm x, biết
\(2.2.\frac{-2}{\frac{3}{X}}\)=\(\frac{4}{\frac{9}{-10}}\)
2.2.\(\frac{-2}{\frac{3}{x}}\)= \(\frac{4}{\frac{9}{-10}}\)
\(\frac{-2}{\frac{3}{x}}\)= \(\frac{4}{\frac{9}{-10}}\): 4
-2/3 : x = -1/90
x = 60