How do you evaluate #\frac { \sqrt { - 72} - 2} { 6}#?

1 Answer
Aug 1, 2017

Since we cannot have a square root of a negative number, we have to bring in complex numbers.

#frac{sqrt(-72) - 2}{6}#

# = frac{i sqrt(72) - 2}{6}#

Simplify the square root
# = frac{i sqrt(36*2) - 2}{6}#

# = frac{6i sqrt2 -2 }{6}#

# =( 3isqrt2 - 1 )/3#

# = isqrt2 - 1/3#