RECOGNIZE HERE THE BASIC FORM (X –Y)2, WHICH EQUALS X2 - 2XY + Y2....
3. Recognize here the basic form (x –y)
2
, which equals x
2
- 2xy +
y
2
.
corresponds here to x, and
So the expression can be simplified to:
Under the radical, recognize the basic form (a + b)(a – b), which
equals a
2
– b
2
.
The expression can be further simplified to:
The correct answer is C.