Question:
Prove by direct method that for any real numbers x, y if x = y, then x2 = y2.
Solution:
Given for any real number x, y if x=y
Now we have to find x2 = y2
Let us assume
p: x=y where x and y are real number
On squaring both sides we get
x2 = y2 : q (Assumption)
Therefore,
p = q
Hence, Proved