How do you simplify #sqrt87#?

1 Answer
Apr 22, 2015

This can be solved easily using a Calculator . We get the answer as #color(green)(approx 9.32738#

But if we are expected to do it without a calculator , here's how it can be done.

#sqrt87 = sqrt(3*29) = sqrt 3 * sqrt 29#

We know that #sqrt 3 approx 1.732#

To find the #color(blue)(sqrt29#, we can use the following formula:

#sqrt(Non-Perfect-Square) approx sqrt(Nearest-Perfect-Square) + (Deviation)/(2*sqrt(Nearest-Perfect-Square))#

The nearest perfect square to 29 is #25#. And the deviation is #29 - 25 = 4#

#sqrt 29 approx sqrt 25 + (4)/(2*sqrt25)#

# approx 5 + (4/10) approx color(blue)(5.4#

Hence we get #sqrt87 approx 1.732 * 5.4 approx color(green)(9.353#