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2 years ago

F(x)= 3x^2+5x-8. Solve the quadratic equation

Mathematics

1 answer:

7nadin3 [17]2 years ago

7 0

Answer:

$\bold{x_1=1\ ,\quad x_2=-\dfrac83}$

Step-by-step explanation:

$3x^2+5x-8=0\quad\implies\quad a=3\,,\ b=5\,,\ c=-8\\\\x=\dfrac{-5\pm\sqrt{5^2-4(3)(-8)}}{2\cdot3}=\dfrac{-5\pm\sqrt{25+96}}{6}=\dfrac{-5\pm\sqrt{121}}{6}\\\\ x_1=\dfrac{-5+11}{6}=1\ ,\qquad x_2=\dfrac{-5-11}{6}=\dfrac{-16}6=-\dfrac83$

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