a=2+_/3 then find the value of a- 1/a
Answers
Answer:
multiply it by 0 and the answer will be 9
Answer:
Hence, the value of a - 1/a = 0
Step-by-step explanation:
Given:-
a = 2 + √3
To find out:-
Value of a - 1/a
Solution:-
We have,
a = 2 + √3
∴ 1/a = 1/2+√3
The denomination = 2+√3
We know that
Rationalising factor of x+√y = x-√y
So, the rationalising factor of 2+√3 = 2-√3
On rationalising the denominator then
1/a = [1/(2+√3)]×[(2-√3)/2-√3)]
1/a = [1(2-√3)]/[(2+√3)(2-√3)]
1/a = (2-√3)/[(2+√3)(2-√3)]
Now, we will apply algebraic Identity in denominator because the denominator is in the form of
(x+y)(x-y) = x^2 - b^2
Where we have to put x = 2 and y = √3
1/a = (2-√3)/[(2)^2 - (√3)^2]
1/a = (2-√3)/(4 - 3)
1/a = (2-√3)/1
1/a = 2-√3
Now, we have to subtract both values a and 1/a, we get
∴ a - 1/a = 2+√3-2-√3
√3 will be cancel because they are in unlike sign , so we will cancel them.
a - 1/a = 2 - 2
a - 1/a = 0
Answer:-
Hence, the value of a - 1/a = 0
Used formulae:-
Rationalising factor of x+√y = x-√y
(x+y)(x-y) = x^2 - y^2
:)