\(\frac{4\times5\times6}{12\times15\times9}\)\(=\frac{2\times2\times5\times6}{2\times6\times3\times5\times9}\)\(=\frac{2}{3\times9}\)\(=\frac{2}{27}\)

\(\frac{6\times8\times11}{33\times16}\)\(=\frac{2\times3\times8\times11}{3\times11\times8\times2}\)\(=\)\(1\)

~ HOK TỐT ~

4×5×612×15×912×15×94×5×6​=2×2×5×62×6×3×5×9=2×6×3×5×92×2×5×6​=23×9=3×92​=227=272​

6×8×1133×1633×166×8×11​=2×3×8×113×11×8×2=3×11×8×22×3×8×11​$=$$1$

Vậy mẫu đâu? :)

a) \(\frac{4x5x6}{12x15x9}\)= \(\frac{4x5x3x2}{4x3x5x3x3x3}\)= \(\frac{2}{27}\)

b) \(\frac{6x8x11}{33x16}\)= \(\frac{6x8x11}{11x3x8x2}\)= \(\frac{6}{6}\)= 1

Bài này ta làm theo cách tính nhanh và trực tiêu cho nhanh

Bài nay

\(\frac{4x5x6}{12x15x9}=\frac{4x5x6}{3x4x3x5x3x3}=\frac{6}{81}=\frac{2}{27}\)

\(\frac{6x8x11}{33x16}=\frac{6x8x11}{11x3x8x2}=\frac{6}{6}=1\)

15 x 7 105         30 x 6 180         28 x 7 196         42 x 5 210

5x7 : 3x2 = (15 : 3).(x7 : x2 )= 5.x(7-2) = 5x5

=15x(6+7)

=15x13

=195

=15x(6+7)

=15x13

=195 nha bạn

\(15.6+15.7\)

\(=15.\left(6+7\right)\)

\(=15.13\)

\(=195\)

chúc bn hk giỏi!

`(4xx5xx6)/(12xx8xx10)=(4xx5xx6)/(6xx2xx4xx2xx5xx2)= 1/(2xx2xx2)=1/8`

120/960 nhé

A=2009+105-6

A=2108

Sửa đề: a = b => x = y

\(P=\left(1-\dfrac{\sqrt{2xy}}{\sqrt{x^2+y^2}}\right)\left(1+\dfrac{\sqrt{2xy}}{\sqrt{x^2+y^2}}\right)\) (ĐK: \(x,y>0\))

\(=1-\left(\dfrac{\sqrt{2xy}}{\sqrt{x^2+y^2}}\right)^2\)

\(=1-\dfrac{\left(\sqrt{2xy}\right)^2}{\left(\sqrt{x^2+y^2}\right)^2}\)

\(=1-\dfrac{2xy}{x^2+y^2}\)

\(=\dfrac{x^2+y^2-2xy}{x^2+y^2}\)

\(=\dfrac{\left(x-y\right)^2}{x^2+y^2}\)

Khi x = y, ta được: \(P=\dfrac{\left(x-y\right)^2}{x^2+y^2}=\dfrac{\left(x-x\right)^2}{x^2+y^2}=0\)

#Urushi

a. \(\frac{3.5.7}{6.21}=\frac{21.5}{21.6}=\frac{5}{6}\)

b. \(\frac{2.3.5}{4.5.6}=\frac{6.5}{4.5.6}=\frac{1}{4}\)