Solve 15x^4-3 - ScanMath

Question

Factor the expression

3 (5 x^{4} - 1)

Evaluate

15 x^{4} - 3

Solution

3 (5 x^{4} - 1)

Show Solution

x_{1} = - \frac{4 125}{5}, x_{2} = \frac{4 125}{5}

Alternative Form

x_{1} \approx - 0.66874, x_{2} \approx 0.66874

Evaluate

15 x^{4} - 3

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

15 x^{4} - 3 = 0

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

15 x^{4} = 0 + 3

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

15 x^{4} = 3

Divide both sides

\frac{15 x ^{4}}{15} = \frac{3}{15}

Divide the numbers

x^{4} = \frac{3}{15}

Cancel out the common factor 3

x^{4} = \frac{1}{5}

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

x = \pm 4 \frac{1}{5}

Simplify the expression

More Steps

Evaluate

4 \frac{1}{5}

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

\frac{4 1}{4 5}

Simplify the radical expression

\frac{1}{4 5}

Multiply by the Conjugate

\frac{4 5 ^{3}}{4 5 \times 4 5 ^{3}}

Simplify

\frac{4 125}{4 5 \times 4 5 ^{3}}

Multiply the numbers

More Steps

Evaluate

45 \times 4 5^{3}

The product of roots with the same index is equal to the root of the product

4 5 \times 5^{3}

Calculate the product

4 5^{4}

Reduce the index of the radical and exponent with 4

5

\frac{4 125}{5}

x = \pm \frac{4 125}{5}

Separate the equation into 2 possible cases

x = \frac{4 125}{5} x = - \frac{4 125}{5}

Solution

x_{1} = - \frac{4 125}{5}, x_{2} = \frac{4 125}{5}

Alternative Form

x_{1} \approx - 0.66874, x_{2} \approx 0.66874

Show Solution