8. Prove that vp is not a rational number, if
is not a perfect square
Answers
Answer:
(a) All numbers that are not rational are considered irrational. An irrational number can be written as a decimal, but not as a fraction. An irrational number has endless non-repeating digits to the right of the decimal point. Here are some irrational numbers:
π=3.141592…
2
=1.414213…
Therefore,
2
is an irrational number.
(b) Let us take a rational number a=
1
2
and an irrational number b=
2
, then their product can be determined as:
a×b=2×
2
=2
2
which is also an irrational number.
Therefore, if a is a rational number and
b
is an irrational number than a
b
is an irrational number.
(c) By definition, a surd is a irrational root of a rational number. So we know that surds are always irrational and they are always roots.
For eg,
2
is a surd since 2 is rational and
2
is irrational.
Surds are numbers left in root form
to express its exact value. It has an infinite number of non-recurring decimals.
Therefore, every surd is an irrational number.
(d) Let us take a positive integer 4, now square root of 4 will be:
4
=2 which is not an irrational number
Hence, the square root of every positive integer is not always irrational.