Solve for m
m = \frac{\sqrt{41} - 1}{4} \approx 1.350781059
m=\frac{-\sqrt{41}-1}{4}\approx -1.850781059
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\left(m^{2}-1\right)\times 4+\left(m-1\right)\times 2-4=0
Calculate 2 to the power of 2 and get 4.
4m^{2}-4+\left(m-1\right)\times 2-4=0
Use the distributive property to multiply m^{2}-1 by 4.
4m^{2}-4+2m-2-4=0
Use the distributive property to multiply m-1 by 2.
4m^{2}-6+2m-4=0
Subtract 2 from -4 to get -6.
4m^{2}-10+2m=0
Subtract 4 from -6 to get -10.
4m^{2}+2m-10=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.
m=\frac{-2±\sqrt{2^{2}-4\times 4\left(-10\right)}}{2\times 4}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 4 for a, 2 for b, and -10 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-2±\sqrt{4-4\times 4\left(-10\right)}}{2\times 4}
Square 2.
m=\frac{-2±\sqrt{4-16\left(-10\right)}}{2\times 4}
Multiply -4 times 4.
m=\frac{-2±\sqrt{4+160}}{2\times 4}
Multiply -16 times -10.
m=\frac{-2±\sqrt{164}}{2\times 4}
Add 4 to 160.
m=\frac{-2±2\sqrt{41}}{2\times 4}
Take the square root of 164.
m=\frac{-2±2\sqrt{41}}{8}
Multiply 2 times 4.
m=\frac{2\sqrt{41}-2}{8}
Now solve the equation m=\frac{-2±2\sqrt{41}}{8} when ± is plus. Add -2 to 2\sqrt{41}.
m=\frac{\sqrt{41}-1}{4}
Divide -2+2\sqrt{41} by 8.
m=\frac{-2\sqrt{41}-2}{8}
Now solve the equation m=\frac{-2±2\sqrt{41}}{8} when ± is minus. Subtract 2\sqrt{41} from -2.
m=\frac{-\sqrt{41}-1}{4}
Divide -2-2\sqrt{41} by 8.
m=\frac{\sqrt{41}-1}{4} m=\frac{-\sqrt{41}-1}{4}
The equation is now solved.
\left(m^{2}-1\right)\times 4+\left(m-1\right)\times 2-4=0
Calculate 2 to the power of 2 and get 4.
4m^{2}-4+\left(m-1\right)\times 2-4=0
Use the distributive property to multiply m^{2}-1 by 4.
4m^{2}-4+2m-2-4=0
Use the distributive property to multiply m-1 by 2.
4m^{2}-6+2m-4=0
Subtract 2 from -4 to get -6.
4m^{2}-10+2m=0
Subtract 4 from -6 to get -10.
4m^{2}+2m=10
Add 10 to both sides. Anything plus zero gives itself.
\frac{4m^{2}+2m}{4}=\frac{10}{4}
Divide both sides by 4.
m^{2}+\frac{2}{4}m=\frac{10}{4}
Dividing by 4 undoes the multiplication by 4.
m^{2}+\frac{1}{2}m=\frac{10}{4}
Reduce the fraction \frac{2}{4} to lowest terms by extracting and canceling out 2.
m^{2}+\frac{1}{2}m=\frac{5}{2}
Reduce the fraction \frac{10}{4} to lowest terms by extracting and canceling out 2.
m^{2}+\frac{1}{2}m+\left(\frac{1}{4}\right)^{2}=\frac{5}{2}+\left(\frac{1}{4}\right)^{2}
Divide \frac{1}{2}, the coefficient of the x term, by 2 to get \frac{1}{4}. Then add the square of \frac{1}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
m^{2}+\frac{1}{2}m+\frac{1}{16}=\frac{5}{2}+\frac{1}{16}
Square \frac{1}{4} by squaring both the numerator and the denominator of the fraction.
m^{2}+\frac{1}{2}m+\frac{1}{16}=\frac{41}{16}
Add \frac{5}{2} to \frac{1}{16} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(m+\frac{1}{4}\right)^{2}=\frac{41}{16}
Factor m^{2}+\frac{1}{2}m+\frac{1}{16}. 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(m+\frac{1}{4}\right)^{2}}=\sqrt{\frac{41}{16}}
Take the square root of both sides of the equation.
m+\frac{1}{4}=\frac{\sqrt{41}}{4} m+\frac{1}{4}=-\frac{\sqrt{41}}{4}
Simplify.
m=\frac{\sqrt{41}-1}{4} m=\frac{-\sqrt{41}-1}{4}
Subtract \frac{1}{4} from 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
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
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
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}