Question

rsolva as seguintes equações do 2º Grau imcompletas :

b) x²=1


c) bx²-50=0


d)7x²-7=0



porfavor respondam todas 3

Answer 1

$b)~~x^2=1\to~~x=\pm~ \sqrt{1} \to~~ x=\pm~1\\\\ \large\boxed{S=\{-1~;~1\}} \\\\\\\\\\c)2x^2-50=0\to~~2x^2=50\to~~x^2= \dfrac{50}{2} \to~~x^2=25\to\\x=\pm~ \sqrt{25} \to~~x=\pm~5\\\\ \large\boxed{S=\{-5~;~5\}}\\\\\\\\\\d)~~7x^2-7=0\to~~7x^2=7\to~~x^2= \dfrac{7}{7} \to~~x^2=1\to\\x=\pm~ \sqrt{1} \to~~ x=\pm~1\\\\ \large\boxed{S=\{-1~;~1\}}$

Answer 2

b)
x²=1
x = √1
x = + 1 e x = - 1
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c)
2x² - 50 = 0
2x² = 50
x² = 50/2
x² = 25
x = √25
x = + 5 e x = - 5
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d)
7x² - 7 = 0
7x² = 7
x² = 7/7
x² = 1
x = √1
x = + 1 e x = - 1