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3 years ago

10

Y=4x^2+x-1 solve using quadratic formula

1 answer:

melamori03 [73]3 years ago

7 0

Answer:

x = sqrt(17)/8 - 1/8 or x = -1/8 - sqrt(17)/8

Step-by-step explanation using the quadratic formula:

Solve for x over the real numbers:

4 x^2 + x - 1 = 0

Divide both sides by 4:

x^2 + x/4 - 1/4 = 0

Add 1/4 to both sides:

x^2 + x/4 = 1/4

Add 1/64 to both sides:

x^2 + x/4 + 1/64 = 17/64

Write the left hand side as a square:

(x + 1/8)^2 = 17/64

Take the square root of both sides:

x + 1/8 = sqrt(17)/8 or x + 1/8 = -sqrt(17)/8

Subtract 1/8 from both sides:

x = sqrt(17)/8 - 1/8 or x + 1/8 = -sqrt(17)/8

Subtract 1/8 from both sides:

Answer: x = sqrt(17)/8 - 1/8 or x = -1/8 - sqrt(17)/8

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3 years ago

Solve the initial value problem y'=2 cos 2x/(3+2y),y(0)=−1 and determine where the solution attains its maximum value.

zloy xaker [14]

Answer:

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Step-by-step explanation:

We are given that

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By using quadratic formula

$x=\frac{-b\pm\sqrt{b^2-4ac}}{2a}$

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When the solution is maximum then y'=0

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