646° Вправа 646Алгебра 8 клас Тарасенкова 2025 · § 15 · стор. 192

646. Розв’яжіть рівняння:

1) ${\displaystyle x^2=}$${\displaystyle 49}$; ${\displaystyle x=}$${\displaystyle \pm 7}$;

2) ${\displaystyle x^2=}$${\displaystyle 64}$; ${\displaystyle x=}$${\displaystyle \pm 8}$;

3) ${\displaystyle 4x^2=}$${\displaystyle 8}$; ${\displaystyle x^2=}$${\displaystyle 2}$; ${\displaystyle x=}$${\displaystyle \pm \sqrt{2}}$;

4) ${\displaystyle x^2=}$${\displaystyle 7}$; ${\displaystyle x=}$${\displaystyle \pm \sqrt{7}}$;

5) ${\displaystyle x^2-9=}$${\displaystyle 0}$; ${\displaystyle x^2=}$${\displaystyle 9}$; ${\displaystyle x=}$${\displaystyle \pm 3}$;

6) ${\displaystyle x^2-5=}$${\displaystyle 0}$; ${\displaystyle x^2=}$${\displaystyle 5}$; ${\displaystyle x=}$${\displaystyle \pm \sqrt{5}}$;

7) ${\displaystyle x^2=}$${\displaystyle -3<0}$; коренів немає;

8) ${\displaystyle x^2+12=}$${\displaystyle 0}$; ${\displaystyle x^2=}$${\displaystyle -12<0}$; коренів немає.