
03-02-2008
Shmads is right- you CAN NOT simply add them together, you must simplify first. The easiest way to see this is to break everything down into it's Prime Factorizations.
squ(28) + squ(63) = squ(4 * 7) + squ(9 * 7)
From here, you can pop out a 4 from the first radical, and 9 from the other, turning the problem into...
2*squ(7) + 3*squ(7) = 5*squ(7)
Simply enough, right?
As far as the others....
2.) squ(44) - squ(11) = squ(4*11) - squ(11) = 2*squ(11) - squ(11) = squ(11)
3.) squ(14) - squ(2/7) = squ(14) - squ(14/49) [simply multiply the top and bottom by 1, in the form of 7/7] = squ(14) - 1/7 *squ(14) = 6/7 * squ(14)
4.) 2*squ(32) + 3*squ(50) - 3*squ(18) = 2*squ(16*2) + 3*squ(25*2) - 3*squ(9*2) = 8*squ(2) + 15*squ(2) - 9*squ(2) = 14*squ(2)
There you go. Should make sense. |