1
______
√7 - 2
The number obtained on rationalizing the denominator of the below one is :-
A √7+2
____
3
B √7-2
____
3
C √7+2
____
5
D √7+2
____
45
______
√7 - 2
The number obtained on rationalizing the denominator of the below one is :-
A √7+2
____
3
B √7-2
____
3
C √7+2
____
5
D √7+2
____
45
Answers & Comments
Step-by-step explanation:
Correct option is A)
We use the identity (a+
b
)(a−
b
)=a
2
−b.
Multiply and divide
7
−2
1
by
7
+2 to get
7
−2
1
×
7
+2
7
+2
=
7−4
7
+2
=
3
7
+2
Hence, option A.