Question

resolva a equações do 2° x²+2x- 3=0
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Answer 1

Resposta:

x2*+2x-3=

x= -2+-√4+12/2

x=-2+-4/2

x'= -2+4÷2=2÷2=1

x"=-2-4÷2= -6÷2= -3

Answer 2

Resposta:

S = {1 , − 3}

Explicação passo-a-passo:

$x^2+2x-3=0\\a=1\\b=2\\c=-3\\\boxed{\Delta = b^2-4\times a\times c}\\\Delta = 2^2-4\times 1\times (-3)\\\Delta = 4+12\\\Delta = 16\\\text{Se \Delta > 0 , a equacao tem duas ra\'izes reais e diferentes.}\\\boxed{x =\dfrac{-b\pm\sqrt{\Delta}}{2\cdot a}}\\x= \dfrac{-2\pm\sqrt{16}}{2\times 1}\\x'= \dfrac{-2 + 4}{2\times 1}=\dfrac{2}{2}=1\\x''= \dfrac{-2 - 4}{2\times 1}=\dfrac{-6}{2}=-3\\S = \{1 , - 3\}$