Solve 7a^3-(a 1) - ScanMath

Question

Simplify the expression

7 a^{3} - a

Evaluate

7 a^{3} - (a \times 1)

Solution

7 a^{3} - a

Show Solution

a (7 a^{2} - 1)

Evaluate

7 a^{3} - (a \times 1)

Any expression multiplied by 1 remains the same

7 a^{3} - a

Rewrite the expression

a \times 7 a^{2} - a

Solution

a (7 a^{2} - 1)

Show Solution

a_{1} = - \frac{7}{7}, a_{2} = 0, a_{3} = \frac{7}{7}

Alternative Form

a_{1} \approx - 0.377964, a_{2} = 0, a_{3} \approx 0.377964

Evaluate

7 a^{3} - (a \times 1)

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

7 a^{3} - (a \times 1) = 0

Any expression multiplied by 1 remains the same

7 a^{3} - a = 0

Factor the expression

a (7 a^{2} - 1) = 0

Separate the equation into 2 possible cases

a = 0 7 a^{2} - 1 = 0

Solve the equation

More Steps

Evaluate

7 a^{2} - 1 = 0

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

7 a^{2} = 0 + 1

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

7 a^{2} = 1

Divide both sides

\frac{7 a ^{2}}{7} = \frac{1}{7}

Divide the numbers

a^{2} = \frac{1}{7}

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

a = \pm \frac{1}{7}

Simplify the expression

More Steps

Evaluate

\frac{1}{7}

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

\frac{1}{7}

Simplify the radical expression

\frac{1}{7}

Multiply by the Conjugate

\frac{7}{7 \times 7}

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

\frac{7}{7}

a = \pm \frac{7}{7}

Separate the equation into 2 possible cases

a = \frac{7}{7} a = - \frac{7}{7}

a = 0 a = \frac{7}{7} a = - \frac{7}{7}

Solution

a_{1} = - \frac{7}{7}, a_{2} = 0, a_{3} = \frac{7}{7}

Alternative Form

a_{1} \approx - 0.377964, a_{2} = 0, a_{3} \approx 0.377964

Show Solution