2x^2-(1/2)x-(3/2)=0
Can someone please show me a step by step solution to solving this using the quadratic formula. I'm having trouble incorporating the fractions into it.
Can someone please show me a step by step solution to solving this using the quadratic formula. I'm having trouble incorporating the fractions into it.
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Hello,
2x² – (½)x – (3/2) = 0
If you are troubled with fractions, just get rid of it! Multiply the whole equation by 2 !
2x² – (½)x – (3/2) = 0
4x² – x – 3 = 0
Then apply quadratic formula:
4x² – x – 3 = 0
a=4 b=-1 c=-3
Discriminant ∆ = b² – 4ac = (-1)² – 4×4×(-3) = 1 + 48 = 49 = 7²
Thus the roots:
x₁ = (-b – √∆)/(2a) = [-(-1) – 7]/(2×4) = -6/8 = -¾
x₂ = (-b + √∆)/(2a) = [-(-1) + 7]/(2×4) = 8/8 = 1
= = = = == = = = = = = = = == = = = = = =
Now if you insist on using the fractions:
2x² – (½)x – (3/2) = 0
a=2 b=-½ c=-3/2
Discriminant ∆ = b² – 4ac = (-½)² – 4×2×(-3/2) = ¼ + 12 = 49/4 = (7/2)²
Thus the roots:
x₁ = (-b – √∆)/(2a) = [-(-½) – (7/2)]/(2×2) = (½ – 7/2)/4 = -6/8 = -¾
x₂ = (-b + √∆)/(2a) = [-(-½) + (7/2)]/(2×2) = (½ + 7/2)/4 = 8/8 = 1
Regards,
Dragon.Jade :-)
2x² – (½)x – (3/2) = 0
If you are troubled with fractions, just get rid of it! Multiply the whole equation by 2 !
2x² – (½)x – (3/2) = 0
4x² – x – 3 = 0
Then apply quadratic formula:
4x² – x – 3 = 0
a=4 b=-1 c=-3
Discriminant ∆ = b² – 4ac = (-1)² – 4×4×(-3) = 1 + 48 = 49 = 7²
Thus the roots:
x₁ = (-b – √∆)/(2a) = [-(-1) – 7]/(2×4) = -6/8 = -¾
x₂ = (-b + √∆)/(2a) = [-(-1) + 7]/(2×4) = 8/8 = 1
= = = = == = = = = = = = = == = = = = = =
Now if you insist on using the fractions:
2x² – (½)x – (3/2) = 0
a=2 b=-½ c=-3/2
Discriminant ∆ = b² – 4ac = (-½)² – 4×2×(-3/2) = ¼ + 12 = 49/4 = (7/2)²
Thus the roots:
x₁ = (-b – √∆)/(2a) = [-(-½) – (7/2)]/(2×2) = (½ – 7/2)/4 = -6/8 = -¾
x₂ = (-b + √∆)/(2a) = [-(-½) + (7/2)]/(2×2) = (½ + 7/2)/4 = 8/8 = 1
Regards,
Dragon.Jade :-)
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2x^2-(1/2)x-(3/2)=0 get rid of the fractions - multiply all by 2
4x^2 -x - 3=0 factor - how do you get the product 4?
(2x - )(2x + )
or
(4x + ) (x - )
what factors will give you the product -3? -1,3 or 1,-3
puzzle - where can you put these pairs in the brackets to get a product
of -3 and a SUM of -1 ?
(4x + 3 ) (x - 1 ) = 0
2 solutions
(4x + 3 ) = 0
or (x - 1 ) = 0
take it from there
4x^2 -x - 3=0 factor - how do you get the product 4?
(2x - )(2x + )
or
(4x + ) (x - )
what factors will give you the product -3? -1,3 or 1,-3
puzzle - where can you put these pairs in the brackets to get a product
of -3 and a SUM of -1 ?
(4x + 3 ) (x - 1 ) = 0
2 solutions
(4x + 3 ) = 0
or (x - 1 ) = 0
take it from there
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Make things a bit easier by removing the fractions.
Multiplying by 2 we get:
4x² - x - 3 = 0
=> (4x + 3)(x - 1) = 0
i.e. x = -3/4 or x = 1
Using the formula we get:
x = {1 ± √[(-1)² - 4(4)(-3)]}/8
=> x = [1 ± √(1 + 48)]/8
=> x = (1 ± √49)/8
i.e. x = (1 ± 7)/8
so, x = -3/4 or 1 as before.
:)>
Multiplying by 2 we get:
4x² - x - 3 = 0
=> (4x + 3)(x - 1) = 0
i.e. x = -3/4 or x = 1
Using the formula we get:
x = {1 ± √[(-1)² - 4(4)(-3)]}/8
=> x = [1 ± √(1 + 48)]/8
=> x = (1 ± √49)/8
i.e. x = (1 ± 7)/8
so, x = -3/4 or 1 as before.
:)>
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Simplify the expression...
2^(2x) * 2^(-1) - 3 * 2^x * 2^(-1) + 1 = 0
2^(2x)/2 - 3 * 2^(x)/2 + 1 = 0
Multiply each term by 2 to get:
2^(2x) - 3 * 2^(x) + 2 = 0
Let u = 2^x. This gives us:
(2^x)² - 3(2^x) + 2 = 0
u² - 3u + 2 = 0
Factoring..
(u - 2)(u - 1) = 0
By zero-product property:
u - 2 = 0 and u - 1 = 0
u = 2 and u = 1
Finally, since u = 2^x..
2^x = 2 and 2^x = 1
x = 1 and x = 0
2^(2x) * 2^(-1) - 3 * 2^x * 2^(-1) + 1 = 0
2^(2x)/2 - 3 * 2^(x)/2 + 1 = 0
Multiply each term by 2 to get:
2^(2x) - 3 * 2^(x) + 2 = 0
Let u = 2^x. This gives us:
(2^x)² - 3(2^x) + 2 = 0
u² - 3u + 2 = 0
Factoring..
(u - 2)(u - 1) = 0
By zero-product property:
u - 2 = 0 and u - 1 = 0
u = 2 and u = 1
Finally, since u = 2^x..
2^x = 2 and 2^x = 1
x = 1 and x = 0
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x = [0.5+-sqrt(0.5^2 + 4*2*3/2)]/4
x = [0.5+-sqrt(12.25)]/4
x = [0.5+-sqrt(12.25)]/4