(sqrt3+sqrt5)^2

14sqrt20-3sqrt125.....so we have...

14√(4*5) - 3√(25*5) =

14(2)√5 - 3(5)√5 =

28√5 - 15√5 =

13√5

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cubedroot 54+cubedroot 16 =

³√54 + ³√16 =

³√(27*2) + ³√(8*2)  =

(3)³√(2) + (2)³√(2)  =

(5) ³√(2)

(sqrt3+sqrt5)^2 --> 

(sqrt3+sqrt5)(sqrt3+sqrt5) -->

sqrt(9) + sqrt(15) + sqrt(15) + sqrt(25) -->

3 + 2sqrt(15) + 5 -->

8 + 2sqrt(15)

Thank you!

and the other one..?

I assume it should be (14√x+3√y)^2:

If so:

(14√x+3√y)(14√x+3√y)

196sqrt(x*x) + 42sqrt(xy) + 42sqrt(xy) + 9sqrt(y*y)

196x + 42sqrt(xy) + 42sqrt(xy) + 9y

196x + 84sqrt(xy) + 9y

14√x+3√y

This one can't be simplified any more, Nataszaa. We can't add unlike radicals.

thanks so much! you helped so much!

14sqrt20-3sqrt125

cubedroot 54+cubedroot 16

can you do these CPhill?

and thank you for correcting that!

youre a life saver! :D

what about the other one CPhill?