Zadanie 17.
a) 8x² = 2|: 8
x² = [tex]\frac{2}{8}[/tex]
x = [tex]\sqrt{\frac{2}{8} }[/tex]
x = [tex]\frac{1}{2}[/tex]
b) (5x + 3)² = 0|: √
5x + 3 = 0
5x = -3|: 5
x = - [tex]\frac{3}{5}[/tex]
c) (3 - x)(2x - 3) = 0
3 - x = 0 v 2x - 3 = 0
-x = -3|× (-1) 2x = 3|: 2
x = 3 x = [tex]\frac{3}{2}[/tex]
x = 1 [tex]\frac{1}{3}[/tex]
x ∈ {1 [tex]\frac{1}{3}[/tex], 3}
d) x² + 6x + 9 = 0
(x + 3)² = 0|: √
x + 3 = 0
x = -3
e) x² = 9x
x² - 9x = 0
x(x - 9) = 0
x = 0 v x - 9 = 0
x = 9
x ∈ {0,9}
f) 5x² - 15 = 0|: 5
x² - 3 = 0
x² = 3
x = √3 v x = -√3
x ∈ {-√3, √3}
g) x(x - 10) = -25
x = -25 v x - 10 = -25
x = -25 + 10
x = -15
x ∈ {-25, -15}
h) (8x + 12)([tex]\frac{1}{2}[/tex]x + 3) = 0
8x + 12 = 0 v [tex]\frac{1}{2}[/tex]x + 3 = 0
8x = -12|: 8 [tex]\frac{1}{2}[/tex]x = -3|× 2
x = -[tex]\frac{12}{8}[/tex] x = -6
x = 1 [tex]\frac{1}{2}[/tex]
x ∈ {-6, 1 [tex]\frac{1}{2}[/tex]}
