Solve 3x^2x 7-2=15

Question

Solve the equation

x = \frac{3 7497}{21}

Alternative Form

x \approx 0.931987

Evaluate

3 x^{2} \times x \times 7 - 2 = 15

Multiply

More Steps

Evaluate

3 x^{2} \times x \times 7

Multiply the terms

21 x^{2} \times x

Multiply the terms with the same base by adding their exponents

21 x^{2 + 1}

Add the numbers

21 x^{3}

21 x^{3} - 2 = 15

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

21 x^{3} = 15 + 2

Add the numbers

21 x^{3} = 17

Divide both sides

\frac{21 x ^{3}}{21} = \frac{17}{21}

Divide the numbers

x^{3} = \frac{17}{21}

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

3 x^{3} = 3 \frac{17}{21}

Calculate

x = 3 \frac{17}{21}

Solution

More Steps

Evaluate

3 \frac{17}{21}

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

\frac{3 17}{3 21}

Multiply by the Conjugate

\frac{3 17 \times 3 2 1 ^{2}}{3 21 \times 3 2 1 ^{2}}

Simplify

\frac{3 17 \times 3 441}{3 21 \times 3 2 1 ^{2}}

Multiply the numbers

More Steps

Evaluate

317 \times 3441

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

3 17 \times 441

Calculate the product

37497

\frac{3 7497}{3 21 \times 3 2 1 ^{2}}

Multiply the numbers

More Steps

Evaluate

321 \times 3 2 1^{2}

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

3 21 \times 2 1^{2}

Calculate the product

3 2 1^{3}

Reduce the index of the radical and exponent with 3

21

\frac{3 7497}{21}

x = \frac{3 7497}{21}

Alternative Form

x \approx 0.931987

Show Solution