Question

Bài 1 Tính

346 - [ 124 +30 : ( 5^8 :5^7 ) . 2^2.1018^0 ]

Bài 2 Tìm x

x ^17 = x

Bài 3

A = 2 +2^2+2^3+...+2^50

B= 3+3^2+3^3+...+ 3^50

C= 2^2+2^4+2^6+...+2^50

Ai nhanh và đúng nhất mình tích cho

Answer 1

1/ \(346-\left[124+30:\left(5^8:5^7\right).2^2.1018^0\right]\)

\(=346-\left[124+30:5.4.1\right]\)

\(=346-\left[124+6.4.1\right]\)

\(=346-\left[124+24\right]\)

\(=346-148\)

\(=198\)

2/ \(x^{17}=x\)

\(\Leftrightarrow x\in\left\{0;1\right\}\)

3/

a/ \(A=2+2^2+..........+2^{50}\)

\(\Leftrightarrow2A=2^2+2^3+..........+2^{51}\)

\(\Leftrightarrow2A-A=\left(2^2+2^3+.......+2^{51}\right)-\left(2+2^2+......+2^{51}\right)\)

\(\Leftrightarrow A=2^{51}-2\)

b,c tương tự