Question

[Hello Mine]

2.3.4.5 + 4.6.8.10 + 6.9.12.15 / 2.3.4.5 + 6.8.10.12 + 9.12.15.18

Answer 1

[Lê Bùi]

\(A=\dfrac{2.3.4.5+4.6.8.10+6.9.12.15}{2.3.4.5+6.8.10.12+9.12.15.18}\)

\(A=\dfrac{2.3.4.5+2.2.2.3.2.4.2.5.+3.2.3.3.3.4.3.5}{2.3.4.5+2.2.2.3.2.4.2.5+3.3.3.4.3.5.3.6}\)

\(A=\dfrac{2.3.4.5+2^4.2.3.4.5.+3^4.2.3.4.5}{2.3.4.5+2^4.2.3.4.5+3^4.3.4.5.6}\)

\(A=\dfrac{\left(1+2^4+3^4\right)2.3.4.5}{\left(2+2^5+3^4.6\right)3.4.5}\)

\(A=\dfrac{\left(1+2^4+3^4\right)2}{\left(1+2^4+3^5\right).2}\)

\(A=\dfrac{1+2^4+3^4}{1+2^4+3^5}=\dfrac{1+16+81}{1+16+243}=\dfrac{49}{130}\)

Answer 2

[Siêu sao bóng đá]

\(\dfrac{2.3.4.5+4.6.8.10+6.9.12.15}{2.3.4.5+6.8.10.12+9.12.15.18}\)

\(=\dfrac{4.6.8.10+6.9.12.15}{6.8.10.12+9.12.15.18}\)

\(=\dfrac{1}{3}\)

Kết quả là \(\dfrac{1}{3}\)vì: \(6.8.10.12:4.6.8.10=12:4=3\)

\(9.12.15.18:6.9.12.15=18:6=3\)

Khi cộng vào thì thương không thay đổi và bằng \(\dfrac{1}{3}\)