Disprove a statement
Im being asked to disprove: If X and Y are positive real numbers, then the SqRt( X+Y) = SqRt(X) + SqRt(Y). As a counterexample, would letting x= 25 and Y=9 be acceptable? Since SqRt(x+y) would equal SqRt(34) and SqRt(X) + SqRt(Y)= 5+3=8 and there not equal?
Yes, this will work.
Originally Posted by nikie1o2
If you want an even simpler counterexample, consider
The more algebraic proof would be to square both sides of the equation and show them they are not the same.