Question

If x and y are rational numbers then show that the following are also rational numbers:
1.x square - y square
2.x-y
3.x by y where y is not equal to 0
4.x+y

Answer 1

Answer:

Step-by-step explanation:

1.x²-y²= (x-y) (x+y)

in this case  difference of 2 rational numbers is a rational number and sum of 2 rational numbers is a rational number so (x-y)(x+y) =x²-y² is a rational number

2.x-y

difference of 2 rational numbers is a rational number so x-y is a rational number

3.x÷y

division of 2 rational numbers is also a rational nmber so x÷y is  a rationa number

4. x+y

sum of 2 rational numbers is a rational number so x+y is a rational number