Question

add (X + Y ) , (X - Y) ​

Answer 1

Answer:

2X (ans)

Step-by-step explanation:

= ( X + Y ) + ( X - Y)

= X + Y+ X - Y

= 2X.

Answer 2

Step-by-step explanation:

(x+y) + (x-y) = x + y + x - y = 2x

But this may not be the question you meant to ask.

Were you perhaps thinking of (x + y) (x - y) ?

This is a very important identity, which resolves as follows:

(x+y)(x−y)=x2+yx−xy−y2=x2−y2

This is known as the ‘difference of two squares’. Whenever you see (x + y) (x - y), you know that it means x2−y2

This means that anything - 1 becomes an easy to resolve problem, because 1 is the square of itself.

So, 999999 can easily be factored as 1001 * 999, on the grounds that it is 1000000–1, and is therefore (1000 + 1) * (1000 - 1).