4x² + 17 = 4x
Put everything on the left by subtracting 4x from both sides:
4x² - 4x + 17 = 0
Now use the quadratic formula to solve...
x = [ -b ± sqrt( b² - 4ac ) ] / 2a
a = 4
b = -4
c = 17
x = [ -(-4) ± sqrt( (-4)² - 4(4)(17) ) ] / 2(4)
x = [ 4 ± sqrt( 16 - 272 ) ] / 8
x = [ 4 ± sqrt( -256 ) ] / 8
x = [ 4 ± sqrt( 256 ) * sqrt(-1) ] / 8
x = ( 4 ± 16i ] / 8
x = 4/8 ± 16i/8
x = ½ ± 2i
2006-12-14 11:12:43
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answer #1
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answered by Puzzling 7
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So the equation is: 4x^2 + 17 = 4x
First you have to put the equation in the form of the general quadratic equation: ax^2 + bx + c = 0
In order to do that subtract 4x from both sides:
4x^2 -4x + 17 = 0
Now use the quadratic formula: [-b +- {(b^2-4ac)}^.5]/2a
Fill in the numbers: [-(-4) +- {((-4)^2-4*4*17)}^.5]/2*4
Simplifying the numbers in the square root you get:
-256.
The square root of a negative number is always imaginary; therefore, the solution is going to be complex (as you stated in the question). Complex numbers are stated in the form a + bi. A is known as the real part while b is known as the imaginary part.
The square root of -256 is the square root of 256 times i. The square root of 256 is 16 so the square root of -256 is 16i.
Put this back into the equation: 4 +- 16i is the numerator. 8 is the denominator. The solution is 4/8 +- 16i/8 . Simplify that to get 1/2 +- 2i.
So the solution is: 1/2 +- 2i
Splitting it up gives you : 1/2 + 2i
1/2 - 2i
2006-12-14 11:30:40
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answer #2
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answered by Jose N 2
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complete the sqaure 9(x -3)^2 +4 9 we take out from 9x^2-54x so we get x^2 -6x we then complete the sq. (x+(b/2)) the place b is now -6x so we get so some distance 9(x -3)^2 in case you distinctive out the bracket we get 9x^2 -54x +80 one we desire 80 5 so we upload 4 subsequently we get 9((x-3)^2) +4 to clean up for x we rearrange start up with the 4 so we get 9(x-3)^2 = -4 this is going to supply 2 complicated roots (x-3)^2 = (-4/9) x-3=+-sqrt(-4/9) x= +-sqrt(-4/9)+3 i = sqrt(-a million) so we've x = +-sqrt(4/9)i+3 or 3+-sqrt(4/9)i
2016-12-30 10:21:28
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answer #3
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answered by ? 3
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4x^2 - 4x + 17 (ax^2 + bx + c)
Delta = b^2 - 4ac = 256
Solution = [-b +/- sqrt(delta)] / 2a
Ans : 20/8 OR -12/8
2006-12-14 11:14:43
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answer #4
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answered by NIK..! 5
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if you mean a+bi as a complex number, it would be difficult because it has a real answer x=1/2
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sorry i confused the +/- signs the answers are 1/2 + 2i and 1/2 - 2i
2006-12-14 11:13:39
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answer #5
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answered by photojenny 2
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a:=4
b:=-4
c=17
x1=(-b+sqr(b^2-4ac))/2a
x2=(-b-sqr(b^2-4ac))/2a
==>
x1= (4+sqrt(16-272))/8 =0.5+2i
x2= (4-sqrt(16-272))/8 =0.5-2i
2006-12-14 11:21:31
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answer #6
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answered by Anonymous
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.5 +- 2i
2006-12-14 11:13:55
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answer #7
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answered by crossndunk 3
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