Question

Решить уравнение:
1) х²-7=0;
2)3х²-7=0;
3)-0,3у²+0,39=0;
4)-у²+6=0;
4)-4х²+19=0

Answer 1

$x^2-7=0 \ x^2=7 \ x=pm sqrt{7}$

$3x^2-7=0 \ 3x^2=7 \ x^2= frac{7}{3} \ x=pm sqrt{ frac{7}{3} }$

$-0.3y^2+0.39=0 \ -0.3y^2=-0.39 \ y^2=1.3 \ y=pm sqrt{1.3}$

$-y^2+6=0 \ y^2=6 \ y=pm sqrt{6}$

$-4x^2+19=0 \ 4x^2=19 \ x^2=4.75 \ x=pm sqrt{4.75}$