Byju's Answer
Standard IX
Mathematics
Rationalisation
Examine, if ...
Question
Examine, if
(
5
+
√
5
)
(
5
−
√
5
)
is rational or irrational .
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Solution
Let
x
=
(
5
+
√
5
)
(
5
−
√
5
)
x
=
25
−
5
=
20
is a rational number.
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