Solve for λ
\lambda =4\sqrt{3}+8\approx 14.92820323
\lambda =8-4\sqrt{3}\approx 1.07179677
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4\times \left(2\times \frac{\lambda -4}{4}\right)^{2}+32\left(-\frac{\lambda }{4}\right)=0
Multiply both sides of the equation by 4.
4\times \left(\frac{\lambda -4}{2}\right)^{2}+32\left(-\frac{\lambda }{4}\right)=0
Cancel out 4, the greatest common factor in 2 and 4.
4\times \frac{\left(\lambda -4\right)^{2}}{2^{2}}+32\left(-\frac{\lambda }{4}\right)=0
To raise \frac{\lambda -4}{2} to a power, raise both numerator and denominator to the power and then divide.
\frac{4\left(\lambda -4\right)^{2}}{2^{2}}+32\left(-\frac{\lambda }{4}\right)=0
Express 4\times \frac{\left(\lambda -4\right)^{2}}{2^{2}} as a single fraction.
\frac{4\left(\lambda -4\right)^{2}}{2^{2}}-8\lambda =0
Cancel out 4, the greatest common factor in 32 and 4.
\frac{4\left(\lambda -4\right)^{2}}{2^{2}}+\frac{-8\lambda \times 2^{2}}{2^{2}}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply -8\lambda times \frac{2^{2}}{2^{2}}.
\frac{4\left(\lambda -4\right)^{2}-8\lambda \times 2^{2}}{2^{2}}=0
Since \frac{4\left(\lambda -4\right)^{2}}{2^{2}} and \frac{-8\lambda \times 2^{2}}{2^{2}} have the same denominator, add them by adding their numerators.
\frac{4\lambda ^{2}-32\lambda +64-32\lambda }{2^{2}}=0
Do the multiplications in 4\left(\lambda -4\right)^{2}-8\lambda \times 2^{2}.
\frac{4\lambda ^{2}-64\lambda +64}{2^{2}}=0
Combine like terms in 4\lambda ^{2}-32\lambda +64-32\lambda .
\frac{4\lambda ^{2}-64\lambda +64}{4}=0
Calculate 2 to the power of 2 and get 4.
16-16\lambda +\lambda ^{2}=0
Divide each term of 4\lambda ^{2}-64\lambda +64 by 4 to get 16-16\lambda +\lambda ^{2}.
\lambda ^{2}-16\lambda +16=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
\lambda =\frac{-\left(-16\right)±\sqrt{\left(-16\right)^{2}-4\times 16}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -16 for b, and 16 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
\lambda =\frac{-\left(-16\right)±\sqrt{256-4\times 16}}{2}
Square -16.
\lambda =\frac{-\left(-16\right)±\sqrt{256-64}}{2}
Multiply -4 times 16.
\lambda =\frac{-\left(-16\right)±\sqrt{192}}{2}
Add 256 to -64.
\lambda =\frac{-\left(-16\right)±8\sqrt{3}}{2}
Take the square root of 192.
\lambda =\frac{16±8\sqrt{3}}{2}
The opposite of -16 is 16.
\lambda =\frac{8\sqrt{3}+16}{2}
Now solve the equation \lambda =\frac{16±8\sqrt{3}}{2} when ± is plus. Add 16 to 8\sqrt{3}.
\lambda =4\sqrt{3}+8
Divide 16+8\sqrt{3} by 2.
\lambda =\frac{16-8\sqrt{3}}{2}
Now solve the equation \lambda =\frac{16±8\sqrt{3}}{2} when ± is minus. Subtract 8\sqrt{3} from 16.
\lambda =8-4\sqrt{3}
Divide 16-8\sqrt{3} by 2.
\lambda =4\sqrt{3}+8 \lambda =8-4\sqrt{3}
The equation is now solved.
4\times \left(2\times \frac{\lambda -4}{4}\right)^{2}+32\left(-\frac{\lambda }{4}\right)=0
Multiply both sides of the equation by 4.
4\times \left(\frac{\lambda -4}{2}\right)^{2}+32\left(-\frac{\lambda }{4}\right)=0
Cancel out 4, the greatest common factor in 2 and 4.
4\times \frac{\left(\lambda -4\right)^{2}}{2^{2}}+32\left(-\frac{\lambda }{4}\right)=0
To raise \frac{\lambda -4}{2} to a power, raise both numerator and denominator to the power and then divide.
\frac{4\left(\lambda -4\right)^{2}}{2^{2}}+32\left(-\frac{\lambda }{4}\right)=0
Express 4\times \frac{\left(\lambda -4\right)^{2}}{2^{2}} as a single fraction.
\frac{4\left(\lambda -4\right)^{2}}{2^{2}}-8\lambda =0
Cancel out 4, the greatest common factor in 32 and 4.
\frac{4\left(\lambda -4\right)^{2}}{2^{2}}+\frac{-8\lambda \times 2^{2}}{2^{2}}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply -8\lambda times \frac{2^{2}}{2^{2}}.
\frac{4\left(\lambda -4\right)^{2}-8\lambda \times 2^{2}}{2^{2}}=0
Since \frac{4\left(\lambda -4\right)^{2}}{2^{2}} and \frac{-8\lambda \times 2^{2}}{2^{2}} have the same denominator, add them by adding their numerators.
\frac{4\lambda ^{2}-32\lambda +64-32\lambda }{2^{2}}=0
Do the multiplications in 4\left(\lambda -4\right)^{2}-8\lambda \times 2^{2}.
\frac{4\lambda ^{2}-64\lambda +64}{2^{2}}=0
Combine like terms in 4\lambda ^{2}-32\lambda +64-32\lambda .
\frac{4\lambda ^{2}-64\lambda +64}{4}=0
Calculate 2 to the power of 2 and get 4.
16-16\lambda +\lambda ^{2}=0
Divide each term of 4\lambda ^{2}-64\lambda +64 by 4 to get 16-16\lambda +\lambda ^{2}.
-16\lambda +\lambda ^{2}=-16
Subtract 16 from both sides. Anything subtracted from zero gives its negation.
\lambda ^{2}-16\lambda =-16
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\lambda ^{2}-16\lambda +\left(-8\right)^{2}=-16+\left(-8\right)^{2}
Divide -16, the coefficient of the x term, by 2 to get -8. Then add the square of -8 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
\lambda ^{2}-16\lambda +64=-16+64
Square -8.
\lambda ^{2}-16\lambda +64=48
Add -16 to 64.
\left(\lambda -8\right)^{2}=48
Factor \lambda ^{2}-16\lambda +64. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(\lambda -8\right)^{2}}=\sqrt{48}
Take the square root of both sides of the equation.
\lambda -8=4\sqrt{3} \lambda -8=-4\sqrt{3}
Simplify.
\lambda =4\sqrt{3}+8 \lambda =8-4\sqrt{3}
Add 8 to both sides of the equation.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
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Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
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