Solve 1/sqrt{7}-4

$$\frac{ 1 }{ \sqrt{ 7 } } -4$$

Evaluate

$$\frac{\sqrt{7}}{7}-4\approx -3.622035527$$

Short Solution Steps

Rationalize the denominator of \frac{1}{\sqrt{7}} by multiplying numerator and denominator by \sqrt{7}.

$$\frac{\sqrt{7}}{\left(\sqrt{7}\right)^{2}}-4$$

The square of \sqrt{7} is 7.

$$\frac{\sqrt{7}}{7}-4$$

To add or subtract expressions, expand them to make their denominators the same. Multiply 4 times \frac{7}{7}.

$$\frac{\sqrt{7}}{7}-\frac{4\times 7}{7}$$

Since \frac{\sqrt{7}}{7} and \frac{4\times 7}{7} have the same denominator, subtract them by subtracting their numerators.

$$\frac{\sqrt{7}-4\times 7}{7}$$

Do the multiplications in \sqrt{7}-4\times 7.

$$\frac{\sqrt{7}-28}{7}$$