Solve for a a/(a-1)=-1/(a+1)

$\frac{a}{a - 1} = \frac{- 1}{a + 1}$

Step 1

Move the negative in front of the fraction.

$\frac{a}{a - 1} = - \frac{1}{a + 1}$

Step 2

Multiply the numerator of the first fraction by the denominator of the second fraction. Set this equal to the product of the denominator of the first fraction and the numerator of the second fraction.

$a (a + 1) = (a - 1) \cdot - 1$

Step 3

Solve the equation for $a$ .

Simplify $a (a + 1)$ .

Rewrite.

$0 + 0 + a (a + 1) = (a - 1) \cdot - 1$

Simplify by adding zeros.

$a (a + 1) = (a - 1) \cdot - 1$

Apply the distributive property.

$a \cdot a + a \cdot 1 = (a - 1) \cdot - 1$

Simplify the expression.

Multiply $a$ by $a$ .

$a^{2} + a \cdot 1 = (a - 1) \cdot - 1$

Multiply $a$ by $1$ .

$a^{2} + a = (a - 1) \cdot - 1$

Simplify $(a - 1) \cdot - 1$ .

Simplify by multiplying through.

Apply the distributive property.

$a^{2} + a = a \cdot - 1 - 1 \cdot - 1$

Simplify the expression.

Move $- 1$ to the left of $a$ .

$a^{2} + a = - 1 \cdot a - 1 \cdot - 1$

Multiply $- 1$ by $- 1$ .

$a^{2} + a = - 1 \cdot a + 1$

Rewrite $- 1 a$ as $- a$ .

$a^{2} + a = - a + 1$

Move all terms containing $a$ to the left side of the equation.

Add $a$ to both sides of the equation.

$a^{2} + a + a = 1$

Add $a$ and $a$ .

$a^{2} + 2 a = 1$

Subtract $1$ from both sides of the equation.

$a^{2} + 2 a - 1 = 0$

Use the quadratic formula to find the solutions.

$\frac{- b \pm \sqrt{b^{2} - 4 (a c)}}{2 a}$

Substitute the values $a = 1$ , $b = 2$ , and $c = - 1$ into the quadratic formula and solve for $a$ .

$\frac{- 2 \pm \sqrt{2^{2} - 4 \cdot (1 \cdot - 1)}}{2 \cdot 1}$

Simplify.

Simplify the numerator.

Raise $2$ to the power of $2$ .

$a = \frac{- 2 \pm \sqrt{4 - 4 \cdot 1 \cdot - 1}}{2 \cdot 1}$

Multiply $- 4 \cdot 1 \cdot - 1$ .

Multiply $- 4$ by $1$ .

$a = \frac{- 2 \pm \sqrt{4 - 4 \cdot - 1}}{2 \cdot 1}$

Multiply $- 4$ by $- 1$ .

$a = \frac{- 2 \pm \sqrt{4 + 4}}{2 \cdot 1}$

Add $4$ and $4$ .

$a = \frac{- 2 \pm \sqrt{8}}{2 \cdot 1}$

Rewrite $8$ as $2^{2} \cdot 2$ .

Factor $4$ out of $8$ .

$a = \frac{- 2 \pm \sqrt{4 (2)}}{2 \cdot 1}$

Rewrite $4$ as $2^{2}$ .

$a = \frac{- 2 \pm \sqrt{2^{2} \cdot 2}}{2 \cdot 1}$

Pull terms out from under the radical.

$a = \frac{- 2 \pm 2 \sqrt{2}}{2 \cdot 1}$

Multiply $2$ by $1$ .

$a = \frac{- 2 \pm 2 \sqrt{2}}{2}$

Simplify $\frac{- 2 \pm 2 \sqrt{2}}{2}$ .

$a = - 1 \pm \sqrt{2}$

The final answer is the combination of both solutions.

$a = - 1 + \sqrt{2}, - 1 - \sqrt{2}$

Step 4

The result can be shown in multiple forms.

Exact Form:

$a = - 1 + \sqrt{2}, - 1 - \sqrt{2}$

Decimal Form:

$a = 0.41421356 \dots, - 2.41421356 \dots$

Solve for a a/(a-1)=-1/(a+1)

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