Question

[Thúy Hà Phạm]

Tính các tích sau:

a) 5xy.(-2bx²y)

b) \(\left(\frac{-4}{5}ab^2c\right)\left(-20a^4bx\right)\)

c) \(^{2^3abc.\frac{1}{4}a^2bc^3}\)

d) \(a^3b^3a^2b^2c\)

e) \(2ab.\frac{4}{3}a^2b^4.7abc\)

f) \(\left(-1,5ab^2\right)\frac{1}{4}bca^2b\)

***Lm giúp mk vs mk cần gấp<3

Answer 1

[Trúc Giang]

a) \(5xy.\left(-2bx^2y\right)\)

\(=\left[5.\left(-2\right)\right]\left(x.x^2\right)\left(y.y\right).b\)

\(=-10x^3y^2b\)

b) \(\left(-\frac{4}{5}ab^2c\right)\left(-20a^4bx\right)\)

\(=\left[\left(-\frac{4}{5}\right)\left(-20\right)\right]\left(a.a^{4\:}\right)\left(b^2b\right).c.x\)

\(=16a^5b^3cx\)

c) \(2^3abc.\frac{1}{4}a^2bc^3\)

\(=\left(2^3.\frac{1}{4}\right)\left(aa^{2\:}\right)\left(bb\right)\left(cc^3\right)\)

\(=2a^3b^2c^4\)

d) \(a^3b^3a^2b^2c\)

\(=\left(a^3a^2\right)\left(b^3b^2\right)c\)

\(=a^5b^5c\)

e) \(2ab.\frac{4}{3}a^2b^47abc\)

\(=\left(2.\frac{4}{3}.7\right)\left(aa^{2\: }a\right)\left(bb^4b\right)c\)

\(=\frac{56}{3}a^4b^6c\)

f) \(\left(-1,5ab^2\right)\frac{1}{4}bca^2b\)

\(=\left(-1,5.\frac{1}{4}\right)\left(aa^{2\:}\right)\left(b^2bb\right)\)

\(=-\frac{3}{8}a^3b^4\)