Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
1). 4^x:16^4=32^2
=>2^2x:(2^4)^4=(2^5)^2
=>2^2x:2^16=2^10
=>2^2x=2^10.2^16
=>2^2x=2^26
=>2x=26
=>x=26:2=13
2)Ta có:
+)3^1000=(3^4)^250=81^250
+)5^750=(5^3)^250=125^250
Vì :81^250<125^250 nên 3^1000<5^750
\(\widehat{xOy}+\widehat{yOz}=180^o\\ \Leftrightarrow25^o+\widehat{yOz}=180^o\\ \widehat{yOz}=180^o-25^o=155^o\)
Chọn D
Ta có:\(1001=1000+1=x+1\)
\(x^8-1001x^7+1001x^6+...+1001x^2-1001x+250\\ =x^8-\left(x+1\right)x^7+\left(x+1\right)x^6+...+\left(x+1\right)x^2-\left(x+1\right)x\\ =x^8-x^8-x^7+x^7+x^6+...+x^3+x^2-x^2-x+250\\ =-x+250=-1000+250\\ =-750\)
P(x)=x^8-1001x^7+...-1001x+250
=x^8-x^7(x+1)+x^6(x+1)-...-x(x+1)+250
=x^8-x^8-x^7+x^7+...-x^2-x+250
=250-x
=-750
\(\left(\frac{1}{4}\right)^3\cdot4^3=\left(\frac{1}{4}\cdot4\right)^3=1^3=1\)
\(\frac{1000^4}{250^4}=4^4=256\)
\(2^2\cdot9\cdot\frac{1}{54}\cdot\left(\frac{4}{9}\right)^2=2^2\cdot3^2\cdot2\cdot3^3\cdot\left(\frac{4}{9}\right)^2=\left[\left(2\cdot3\cdot\frac{4}{9}\right)^2\right]\cdot2\cdot3^3=\frac{64}{9}\cdot2\cdot27=384\)
2. a) 2x = 9 => x không thỏa mãn
b) x2 = 9 => x = \(\pm\)3
c) (x + 1)2 = 4 => (x + 1)2 = \(\pm\)22
=> \(\orbr{\begin{cases}x+1=2\\x+1=-2\end{cases}}\Rightarrow\orbr{\begin{cases}x=1\\x=-3\end{cases}}\)
Bài 1 :
\(a,\left(\frac{1}{4}\right)^3.4^3\)
\(=\frac{1}{4^3}.4^3\)
\(=1\)
\(b,\frac{1000^4}{250^4}=\frac{\left(250.4\right)^4}{250^4}=\frac{250^4.4^4}{250^4}=4^4=256\)
\(d,2^2.9.\frac{1}{54}.\left(\frac{4}{9}\right)^2\)
\(=36.\frac{1}{54}.\frac{4^2}{9^2}\)
\(=\frac{18.2.16}{18.3.81}\)
\(=\frac{32}{243}\)
Bài 2 :
\(a,2^x=9\)
\(\Rightarrow\)x không thỏa mãn
\(b,x^2=9\)
\(\Rightarrow x^2=3^2\)
\(\Rightarrow\orbr{\begin{cases}x=3\\x=-3\end{cases}}\)
\(c,\left(x+1\right)^2=4\)
\(\Rightarrow\left(x+1\right)^2=2^2\)
\(\Rightarrow\orbr{\begin{cases}x+1=2\\x+1=-2\end{cases}}\Rightarrow\orbr{\begin{cases}x=1\\x=-3\end{cases}}\)
Học tốt
Ta có:
x = 21000 = 2250.4 = (24)250 = 16250
y = 3750 = 3250.3 = (33)250 = 27250
z = 5500 = 5250.2 = (52)250 = 25250
Vì 27250 > 25250 > 16250 => y > z > x
Vậy ta chon đáp án B
\(5^x+5^{x+1}=750\)
\(5^x=750\)
\(5^x.6=750\)
\(5^x=750:6\)
\(5^x=125\)
\(5^x=5^3\)
\(\Rightarrow x=3\)
5^x + 5^x+1 = 750
<=> 5^x + 5^x . 5 = 750
<=> 5^x.(1+5) = 750
<=> 5^x . 6 = 750
<=> 5^x = 750 : 6 = 125 = 5^3
=> x = 3
x + 750 + 250 = 1000
<=> x + 1000 =1000
=> x = 0
tk mk mk tk lại nha
x+750+250=1000
x+1000=1000
x =1000-1000
x =0