Question

Решите уравнения:
1)
$2x {}^{2} - 5 = 0$
2)
$- x {}^{2} + 3 =$
3)
$(x + 1) {}^{2} - 4 = 0$
4)
$- (x - 2) {}^{2} + 1 = 0$
5)
$- 3(x + 3) {}^{2} + 48 = 0$
6)
$\frac{4}{9} x {}^{2} - 1 = 0$
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Answer 1

1)2x²-5=0

2x²=5

x²=5/2

x²=2.5

x1=√2,5

x2=-√2.5

2)-x²+3=0

-x²=-3 *(-1)

x²=3

x1=√3

x2=-√3

3) (x+1)²-4=0

x²+2x+1²-4=0

x²+2x-3=0

Д=4-4*1*(-3)=4+12=16

x1=\frac{-b+√Д}{2a} =\frac{-2+√16}{2*1}=\frac{-2+4}{2}=\frac{2}2}=1

x2=\frac{-b-√Д}{2a} =\frac{-2-√16}{2*1}=\frac{-2-4}{2}=\frac{-6}2}=-3