How do you evaluate #\sqrt { 8} - 9\sqrt { 128} - 10\sqrt { 32}#?

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Answer 1 · 2017-11-22T13:35:23

See explanation.

If we do the prime factorization of the numbers under root signs we can write that:

#sqrt(8)=2sqrt(2)#

#sqrt(128)=8sqrt(2)# and

#sqrt(32)=4sqrt(2)#

So the expression becomes:

#2sqrt(2)-9*8sqrt(2)-10*4sqrt(2)=#

#sqrt(2)*(2-72-40)=-110sqrt(2)#