CLASS 9 EX-R.1
2.Write two irrational numbers whose sum and product are rational.
Solution: For sum let us take two irrational numbers e.g (4+√5) and (6-√5).
Adding these two numbers we get,
(4+√5)+(6-√5)
=4+√5+6-√5 (Removed the bracket)
=4+6+√5-√5 (Arranged the number)
=10
Also,for product we take the two irrational numbers e.g (3+√3) and (3-√3).
Multiplying these two numbers we get,
(3+√3)(3-√3)
=3 square - √3 square ( Using identy )
=9-3
=6
Therefore, the sum and product of two irrational numbers is 10 and 6 respectively that is
rational numbers.
2.Write two irrational numbers whose sum and product are rational.
Solution: For sum let us take two irrational numbers e.g (4+√5) and (6-√5).
Adding these two numbers we get,
(4+√5)+(6-√5)
=4+√5+6-√5 (Removed the bracket)
=4+6+√5-√5 (Arranged the number)
=10
Also,for product we take the two irrational numbers e.g (3+√3) and (3-√3).
Multiplying these two numbers we get,
(3+√3)(3-√3)
=3 square - √3 square ( Using identy )
=9-3
=6
Therefore, the sum and product of two irrational numbers is 10 and 6 respectively that is
rational numbers.
