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3 years ago

What is the value of b^2-4ac for the following equation 2x^2-2x-1=0

Mathematics

1 answer:

Eva8 [605]3 years ago

8 0

Here a = 2, b = -2, c = -1
b^2-4ac = (-2)^2 - 4(2)(-1)
= 4 +8
= 12

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3 years ago

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zheka24 [161]

Answer:

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Step-by-step explanation:

Let:

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This is and exact equation, because:

$\frac{\partial M(x,y)}{\partial y} =2=\frac{\partial N}{\partial x}$

So, define f(x,y) such that:

$\frac{\partial f(x,y)}{\partial x} =M(x,y)\\\\and\\\\\frac{\partial f(x,y)}{\partial y} =N(x,y)$

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Where g(y) is an arbitrary function of y.

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Substitute into $\frac{\partial f(x,y)}{\partial y} =N(x,y)$

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The solution is f(x,y)=C1

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Solving y using quadratic formula:

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3 years ago