Solve for t
t=\frac{\sqrt{33}+1}{8}\approx 0.843070331
t=\frac{1-\sqrt{33}}{8}\approx -0.593070331
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t+4-4t^{2}-2=0
Add 3 and 1 to get 4.
t+2-4t^{2}=0
Subtract 2 from 4 to get 2.
-4t^{2}+t+2=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.
t=\frac{-1±\sqrt{1^{2}-4\left(-4\right)\times 2}}{2\left(-4\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -4 for a, 1 for b, and 2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
t=\frac{-1±\sqrt{1-4\left(-4\right)\times 2}}{2\left(-4\right)}
Square 1.
t=\frac{-1±\sqrt{1+16\times 2}}{2\left(-4\right)}
Multiply -4 times -4.
t=\frac{-1±\sqrt{1+32}}{2\left(-4\right)}
Multiply 16 times 2.
t=\frac{-1±\sqrt{33}}{2\left(-4\right)}
Add 1 to 32.
t=\frac{-1±\sqrt{33}}{-8}
Multiply 2 times -4.
t=\frac{\sqrt{33}-1}{-8}
Now solve the equation t=\frac{-1±\sqrt{33}}{-8} when ± is plus. Add -1 to \sqrt{33}.
t=\frac{1-\sqrt{33}}{8}
Divide -1+\sqrt{33} by -8.
t=\frac{-\sqrt{33}-1}{-8}
Now solve the equation t=\frac{-1±\sqrt{33}}{-8} when ± is minus. Subtract \sqrt{33} from -1.
t=\frac{\sqrt{33}+1}{8}
Divide -1-\sqrt{33} by -8.
t=\frac{1-\sqrt{33}}{8} t=\frac{\sqrt{33}+1}{8}
The equation is now solved.
t+4-4t^{2}-2=0
Add 3 and 1 to get 4.
t+2-4t^{2}=0
Subtract 2 from 4 to get 2.
t-4t^{2}=-2
Subtract 2 from both sides. Anything subtracted from zero gives its negation.
-4t^{2}+t=-2
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.
\frac{-4t^{2}+t}{-4}=-\frac{2}{-4}
Divide both sides by -4.
t^{2}+\frac{1}{-4}t=-\frac{2}{-4}
Dividing by -4 undoes the multiplication by -4.
t^{2}-\frac{1}{4}t=-\frac{2}{-4}
Divide 1 by -4.
t^{2}-\frac{1}{4}t=\frac{1}{2}
Reduce the fraction \frac{-2}{-4} to lowest terms by extracting and canceling out 2.
t^{2}-\frac{1}{4}t+\left(-\frac{1}{8}\right)^{2}=\frac{1}{2}+\left(-\frac{1}{8}\right)^{2}
Divide -\frac{1}{4}, the coefficient of the x term, by 2 to get -\frac{1}{8}. Then add the square of -\frac{1}{8} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
t^{2}-\frac{1}{4}t+\frac{1}{64}=\frac{1}{2}+\frac{1}{64}
Square -\frac{1}{8} by squaring both the numerator and the denominator of the fraction.
t^{2}-\frac{1}{4}t+\frac{1}{64}=\frac{33}{64}
Add \frac{1}{2} to \frac{1}{64} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(t-\frac{1}{8}\right)^{2}=\frac{33}{64}
Factor t^{2}-\frac{1}{4}t+\frac{1}{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(t-\frac{1}{8}\right)^{2}}=\sqrt{\frac{33}{64}}
Take the square root of both sides of the equation.
t-\frac{1}{8}=\frac{\sqrt{33}}{8} t-\frac{1}{8}=-\frac{\sqrt{33}}{8}
Simplify.
t=\frac{\sqrt{33}+1}{8} t=\frac{1-\sqrt{33}}{8}
Add \frac{1}{8} to both sides of the equation.
Examples
Quadratic equation
{ 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}