Solve 5x^2 4x - 1

Question

Simplify the expression

20 x^{3} - 1

Evaluate

5 x^{2} \times 4 x - 1

Solution

More Steps

Evaluate

5 x^{2} \times 4 x

Multiply the terms

20 x^{2} \times x

Multiply the terms with the same base by adding their exponents

20 x^{2 + 1}

Add the numbers

20 x^{3}

20 x^{3} - 1

Show Solution

x = \frac{3 50}{10}

Alternative Form

x \approx 0.368403

Evaluate

5 x^{2} \times 4 x - 1

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

5 x^{2} \times 4 x - 1 = 0

Multiply

More Steps

Multiply the terms

5 x^{2} \times 4 x

Multiply the terms

20 x^{2} \times x

Multiply the terms with the same base by adding their exponents

20 x^{2 + 1}

Add the numbers

20 x^{3}

20 x^{3} - 1 = 0

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

20 x^{3} = 0 + 1

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

20 x^{3} = 1

Divide both sides

\frac{20 x ^{3}}{20} = \frac{1}{20}

Divide the numbers

x^{3} = \frac{1}{20}

Take the 3 -th root on both sides of the equation

3 x^{3} = 3 \frac{1}{20}

Calculate

x = 3 \frac{1}{20}

Solution

More Steps

Evaluate

3 \frac{1}{20}

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

\frac{3 1}{3 20}

Simplify the radical expression

\frac{1}{3 20}

Multiply by the Conjugate

\frac{3 2 0 ^{2}}{3 20 \times 3 2 0 ^{2}}

Simplify

\frac{2 3 50}{3 20 \times 3 2 0 ^{2}}

Multiply the numbers

More Steps

Evaluate

320 \times 3 2 0^{2}

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

3 20 \times 2 0^{2}

Calculate the product

3 2 0^{3}

Reduce the index of the radical and exponent with 3

20

\frac{2 3 50}{20}

Cancel out the common factor 2

\frac{3 50}{10}

x = \frac{3 50}{10}

Alternative Form

x \approx 0.368403

Show Solution