Question

Câu 1   So sánh

B = 3 ⁷⁵

C = 2¹⁰⁰

Câu 2 Tìm x biết 

{ [ ( 50 - x )  : 2 + 80 ] - 5² . 2 } . 4 = 200

Answer 1

Câu 1: Ta có: \(B=3^{75}=\left(3^3\right)^{25}=27^{25}\)

                     \(C=2^{100}=\left(2^4\right)^{25}=16^{25}\)

Vì 27 > 16 nên 27²⁵>16²⁵

Vậy B > C

Câu 2: \(\left\{\left[\left(50-x\right):2+80\right]-5^2.2\right\}.4=200\)

\(\Leftrightarrow\left[\left(50-x\right):2+80-50\right].4=200\)

\(\Leftrightarrow\left(50-x\right):2+30=50\)

\(\Leftrightarrow\left(50-x\right):2=20\)

\(\Leftrightarrow50-x=40\)

\(\Leftrightarrow x=10\)

Vậy x = 10

Answer 2

\(3^{75}=\left(3^3\right)^{25}=27^{25}\)

\(2^{100}=\left(2^4\right)^{25}=8^{25}\)

Vì \(27^{25}>8^{25}\)

\(\Rightarrow3^{75}>2^{100}\)

Answer 3

Câu 1 :\(B=3^{75}=\left(3^3\right)^{25}=27^{25}\)

\(C=2^{100}=\left(2^4\right)^{25}=16^{25}\)

\(\Rightarrow B>C\)

Câu 2 :

\(\left\{\left[\left(50-x\right):2+80\right]-5^2.2\right\}.4=200\)

\(\Rightarrow\left[\left(50-x\right):2+80\right]=200:4:2:5^2=1\)

\(\Rightarrow\left(50-x\right):2+80=1\)

\(\Rightarrow x=50+79.2\)

\(\Rightarrow x=..........\)