Vì \(ƯCLN\left(a,b\right)=32\)nên \(a=32m,b=32n\)

Trong đó \(\left(m,n\right)=1\)

Khi đó \(a.b=32m.32n=1024m.n\)

\(\Rightarrow\)\(6144=1024.m.n\)

\(\Rightarrow\)\(m.n=6\)

Lại có: \(\left(m,n\right)=1\)nên ta có 4 trường hợp sau:

\(m=1;n=6\Rightarrow a=21;b=192\)

\(m=6;n=1\Rightarrow a=192;b=32\)

\(m=2;n=3\Rightarrow a=64;b=96\)

\(m=3;n=2\Rightarrow a=96;b=64\)

\(2a^2-3ab+b^2=0\)

\(\Leftrightarrow\left(2a^2-2ab\right)-\left(ab-b^2\right)=0\)

\(\Leftrightarrow\left(a-b\right)\left(2a-b\right)=0\)

\(\Leftrightarrow\orbr{\begin{cases}a-b=0\\2a-b=0\end{cases}\Leftrightarrow\orbr{\begin{cases}a=b\\2a=b\end{cases}}}\)

Rồi thay vào mà tính

A KHÁC 0

B KHÁC 0

XIN LỖI MIK VIET SAI

PHẢI LÀ A =0 VÀ B=0

\(in)\

c khó nhất mk lm

\(\frac{a}{b}=\frac{4}{5}\Rightarrow a=4k;b=5k\left(k\in N\right)\Rightarrow BCNN\left(a,b\right)=20k\Rightarrow k=7\)

\(\Rightarrow a=28;b=35\)

Vậy 2 số cần tìm là: a=28; b=35

a=-9

b=-2

hoac a=-2,=-9

1. 

 \(ƯCLN\left(a,b\right)=7\)

\(\Rightarrow a,b\)chia hết cho 7

\(\Rightarrow a,b\in B\left(7\right)\)

\(B\left(7\right)=\left(0;7;14;21;28;35;42;49;56;63;70;77;84;91;98;105...\right)\)

a, vì a+b=56 \(\Rightarrow\)\(a\le56;b\le56\)

\(\Rightarrow a=56;b=0.a=0;b=56\)

\(a=7;b=49.a=49;b=7\)

\(a=14;b=42.a=42;b=14\)

\(a=21;b=35.a=35;b=21\)

\(a=b=28\)

b, a.b=490 \(\Rightarrow a< 490;b< 490\)

\(\Rightarrow\) \(a=7;b=70-a=70;b=7\)

          \(a=14;b=35-a=35;b=14\)

c, BCNN (a,b) = 735

\(\Rightarrow a,b\inƯ\left(735\right)\)

\(Ư\left(735\right)=\left(1;3;5;7;15;21;35;49;105;147;245;735\right)\)

\(\Rightarrow\)\(a=7;b=105-a=105;b=7\)

2. 

a+b=27\(\Rightarrow\)\(a\le27;b\le27\)

ƯCLN(a,b)=3

\(\Rightarrow a,b\in B\left(_{ }3\right)\in\left(0;3;6;9;12;15;18;21;24;27;30;...\right)\)

BCNN(a,b)=60

\(\Rightarrow a,b\inƯ\left(60\right)\in\left(1;2;3;4;5;6;10;12;15;20;60\right)\)

\(\Rightarrow\)\(a=12;b=15-a=15;b=12\)