Question

if a^2-6a-1=0,what will be value of (a-1/a)

Answer 1

Answer :-

a - 1/a = 6

Explanation :-

Given :-

a² - 6a - 1 = 0

To find :-

a - 1/a

Solution :-

a² - 6a - 1 = 0

Transpose - 1 to RHS [ - 1 becomes 1]

⇒ a² - 6a = 1

Taking 'a' as common value

⇒ a(a - 6) = 1

Transpose a to RHS [Multiplication becomes division]

⇒ a - 6 = 1/a

Transpose 1/a to LHS [ 1/a becomes - 1/a]

⇒ a - 6 - 1/a = 0

Transpose - 6 to RHS [ - 6 becomes 6]

⇒ a - 1/a = 6

Note :-

• These type of questions can be solved by just solving the given equation in terms of constants(numbers i.e, 6).

• The given equation can be solved perfectly when you know transposing rules.

• Transposing rules

1. Addition(+) becomes subtraction(-)

2. Subtraction(-) becomes addition(+)

3. Division becomes multiplication

4. Multiplication becomes division