Bài 1:
a: \(=\dfrac{\left(\dfrac{2}{5}\cdot5\right)^7\cdot\left(\dfrac{9}{4}:\dfrac{3}{10}\right)^3}{2^7\cdot5^2+2^9}\)
\(=\dfrac{\left(\dfrac{15}{2}\right)^3}{2^7\left(5^2+2^2\right)}=\dfrac{15^3}{2^3}\cdot\dfrac{1}{2^7\cdot29}=\dfrac{15^3}{2^{10}\cdot29}\)
b: 2x-3y=0 nên 2x=3y
=>x/3=y/2
Đặt x/3=y/2=k
=>x=3k; y=2k
x^2-2y^2=2
=>9k^2-2*4k^2=2
=>k^2=2
TH1: \(k=\sqrt{2}\)
=>\(x=3\sqrt{2};y=2\sqrt{2}\)
TH2: \(k=-\sqrt{2}\)
=>\(x=-3\sqrt{2};y=-2\sqrt{2}\)