\(\frac{12x^2}{11y^2}:\frac{9xy}{4}:\frac{6x^3}{11y}=\frac{12x^2×4×11y}{11y×9xy×6x^3}=\frac{8}{9x^2y}\)

c \(\frac{\left(2x-4\right)\left(x-3\right)}{\left(x-2\right)\left(3x^2-27\right)}=\frac{2\left(x-2\right)\left(x-3\right)}{3\left(x-2\right)\left(x^2-9\right)}\)

\(=\frac{2\left(x-2\right)\left(x-3\right)}{3\left(x-2\right)\left(x-3\right)\left(x+3\right)}=\frac{2}{3\left(x+3\right)}\)

d, \(\frac{x^2+5x+6}{x^2+4x+4}=\frac{\left(x+2\right)\left(x+3\right)}{\left(x+2\right)^2}=\frac{x+3}{x+2}\)

Tương tự với a ; b 

1 + 9 x 8 = 73.

Kích cho tớ nhé!Xin cậu đấy!

1+9x8=80

bạn k mik trước đi rùi mik k lại cho

hứa luôn

1+9x8=1+72=73

9x2x4=72

9x8+4=76

4x2x9-2=70

~HT~ {học tốt}

TL : 

9 x 2 x 4 = 18 x 4 = 72

9 x 8 + 4 = 72 + 4 = 76

4 x 2 x 9 - 2 = 8 x 9 - 2 = 72 - 2 = 70

T I C K cho mình nhé !

~HT~

= 72

= 76

= 70

Hok tốt

a)\(\left(2x+1\right).\left(x-1\right)=2x^2-x-1\)

b) \(\frac{3xy+6x^2y-9xy}{3xy}=\frac{3xy+2x.\left(3xy\right)-3.\left(3xy\right)}{3xy}=\frac{\left(3xy\right).\left(1+2x-3\right)}{3xy}=2x-2=2.\left(x-1\right)\)

\(\left(\frac{4}{5}x^4y^2\right)\left(\frac{5}{9}xy\right)=\left(\frac{4}{5}\cdot\frac{5}{9}\right)\left(x^4x\right)\left(y^2y\right)=\frac{4}{9}x^5y^3\)

\(a,(\frac{4}{5}x^4y^2).(\frac{5}{9}xy)\)

\(=\frac{4}{5}.\frac{5}{9}.x^4.x.y^2.y\)

\(=\frac{4}{9}x^5y^3\)

Học tốt