Tính nhanh : \(A=490-3100\times7^2+90\times7^2+49\times125\times16\)16

Tính (theo mẫu).

Mẫu: \(\dfrac{2\times3\times7}{5\times7\times3}=\dfrac{2}{5}\)

a) \(\dfrac{12\times11\times13}{13\times17\times11}\)                                   b) \(\dfrac{49\times16\times31}{16\times49\times37}\)

tính :\(\frac{1}{1\times2\times3}+\frac{1}{2\times3\times4}+\frac{1}{3\times4\times5}+\frac{1}{4\times5\times6}+\frac{1}{5\times6\times7}+\frac{1}{6\times7\times8}+\frac{1}{7\times8\times9}+\frac{1}{8\times9\times10}\)

Tính: A=\(\frac{49^{24}\cdot125^{10}\cdot2^8-5^{30}\cdot7^{49}\cdot4^5}{5^{29}\cdot16^2\cdot7^{48}}\)

thực hiện phép tính:\(A=\frac{2^{12}\times4^6\times9^2}{2^{12}\times3^6+8^4\times3^5}-\frac{5^{10}\times7^3-25^2\times49^2}{125^3\times7^3+5^9\times14^3}\)

tính nhanh: \(\frac{1\times3\times2\times4\times3\times5\times4\times6\times5\times7}{2\times2\times3\times3\times4\times4\times5\times5\times6\times6}\)

Bài 1:

\(\dfrac{2}{1\times4}+\dfrac{2}{4\times7}+.....+\dfrac{2}{94\times97}\)

Bài 2:

\(6+3\times\left(x-3\right)=24\)

\(x\div0,25+\dfrac{x}{5}+x\times2=1972\)

Tính: \(\frac{49^{24}.125^{10}.2^8-5^{30}.7^{49}.4^5}{5^{29}.16^2.7^{48}}\)    GIUP MINH VOI !!!........ Cam On Cac Ban Nhieu

Bài 1: Tính

a) \(\dfrac{2\times3\times6\times7}{12\times7\times9\times2}\)

b) \(\dfrac{3\times4\times30\times56}{9\times8\times7\times8\times20}\)

(Các bạn tách ra rồi tính)