Solve b^28-1 - ScanMath

Question

Simplify the expression

8 b^{2} - 1

Evaluate

b^{2} \times 8 - 1

Solution

8 b^{2} - 1

Show Solution

b_{1} = - \frac{2}{4}, b_{2} = \frac{2}{4}

Alternative Form

b_{1} \approx - 0.353553, b_{2} \approx 0.353553

Evaluate

b^{2} \times 8 - 1

To find the roots of the expression,set the expression equal to 0

b^{2} \times 8 - 1 = 0

Use the commutative property to reorder the terms

8 b^{2} - 1 = 0

Move the constant to the right-hand side and change its sign

8 b^{2} = 0 + 1

Removing 0 doesn't change the value,so remove it from the expression

8 b^{2} = 1

Divide both sides

\frac{8 b ^{2}}{8} = \frac{1}{8}

Divide the numbers

b^{2} = \frac{1}{8}

Take the root of both sides of the equation and remember to use both positive and negative roots

b = \pm \frac{1}{8}

Simplify the expression

More Steps

Evaluate

\frac{1}{8}

To take a root of a fraction,take the root of the numerator and denominator separately

\frac{1}{8}

Simplify the radical expression

\frac{1}{8}

Simplify the radical expression

More Steps

Evaluate

8

Write the expression as a product where the root of one of the factors can be evaluated

4 \times 2

Write the number in exponential form with the base of 2

2^{2} \times 2

The root of a product is equal to the product of the roots of each factor

2^{2} \times 2

Reduce the index of the radical and exponent with 2

22

\frac{1}{2 2}

Multiply by the Conjugate

\frac{2}{2 2 \times 2}

Multiply the numbers

More Steps

Evaluate

22 \times 2

When a square root of an expression is multiplied by itself,the result is that expression

2 \times 2

Multiply the numbers

4

\frac{2}{4}

b = \pm \frac{2}{4}

Separate the equation into 2 possible cases

b = \frac{2}{4} b = - \frac{2}{4}

Solution

b_{1} = - \frac{2}{4}, b_{2} = \frac{2}{4}

Alternative Form

b_{1} \approx - 0.353553, b_{2} \approx 0.353553

Show Solution