SOLUTION: x^2+2x+9
I have tried x={-2ħsqrt(2^2-4*1*9)}/2*1
(quadratic formula: x={-bħsqrt( b^2-4ac)}/2(a))
Process:
x={-2ħsqrt(2^2-4*1*9)}/2(1)
x={-2ħsqrt(4-36)}/2
x=(-2/2)ħ{sqrt-3
Algebra.Com
Question 251829: x^2+2x+9
I have tried x={-2ħsqrt(2^2-4*1*9)}/2*1
(quadratic formula: x={-bħsqrt( b^2-4ac)}/2(a))
Process:
x={-2ħsqrt(2^2-4*1*9)}/2(1)
x={-2ħsqrt(4-36)}/2
x=(-2/2)ħ{sqrt-32/2}
x=-1ħ(sqrt-32/2)
Looking for -1ħ2i*sqrt(2), but I can't get there.
I need the process to find this imaginary root.
what am I doing wrong?
Answer by jim_thompson5910(35256) (Show Source): You can put this solution on YOUR website!
The trick here lies in simplifying
Start with the given expression
Factor out a negative 1
Break up the square roots using the identity
Replace with (remember )
Now lets simplify :
The goal of simplifying expressions with square roots is to factor the radicand into a product of two numbers. One of these two numbers must be a perfect square. When you take the square root of this perfect square, you will get a rational number.
So let's list the factors of 32
Factors:
1, 2, 4, 8, 16, 32
Notice how 16 is the largest perfect square, so lets factor 32 into 16*2
Factor 32 into 16*2
Break up the square roots using the identity
Take the square root of the perfect square 16 to get 4
This means that the expression simplifies to
So the expression simplifies to (just reintroduce back in)
In other words,
----------------------------------------------------------------------
Going back to , this expression simplifies to . From there, it reduces to
So the solutions are or
RELATED QUESTIONS
Solve 2x^2 + 5x - 1 = 0 by using quadratic formula. Use coefficients, a=2, b=5, c=-1. My... (answered by jim_thompson5910)
solve:
{{{sqrt((x^2+1))+8/sqrt(x^2+1) = sqrt(x^2+9)}}}
(answered by friesr)
{{{ sqrt ( 2x-1 )+ sqrt ( 2-x ) =2 }}} (answered by josgarithmetic)
{{{ sqrt ( 2x-1 )+ sqrt ( 2-x )... (answered by Fombitz)
Determine the equation for h(x), where {{{ h(x) = k*(g-f) }}}
{{{ f(x)= sqrt (x)-2 }}}
(answered by MathLover1)
hi, I am solving by quadraic formula -b sqrt (b2-4ac)/(2a)
x^2+2x=168... (answered by solver91311)
Solve e^2x-10e^x+24=0, it has two solutions.
I am not sure how to solve it,but I tried (answered by ikleyn)
I am trying to solve p2 15p = 54
but I am not getting the answers provided.
I... (answered by stanbon)
1) I need help in solving the following equations.
a)sqrt x-2=1
b)sqrt... (answered by sarah_adam)