Just a quick clarification?

(Problem in comments.)

Question

Just a quick clarification?

(Problem in comments.)

anonymous · Answer

I need to find the conjugate of $$a-\sqrt{a-1}$$

misssunshinexxoxo · Answer

Plugged it in http://www.wolframalpha.com/input/?i=a%E2%88%92a%E2%88%921%E2%88%92%E2%88%92%E2%88%92%E2%88%92%E2%88%9A

anonymous · Answer

I'm not sure if it is $$a+\sqrt{a+1}$$ or $$a-\sqrt{a-1}$$ the lesson I had is not very clear.

anonymous · Answer

I just need to know if when flipping the sign I flip the sign on the inside of the radical?

mathstudent55 · Answer

Only the - between the a and the root changes to +.

anonymous · Answer

Ok thanks @mathstudent55

mathstudent55 · Answer

You're welcome.

$(a - \sqrt{a - 1})(a + \sqrt{a - 1})$ follows the pattern

$(a - b)(a + b) = a^2 + b^2$

The root term will disappear after multiplication.

If you change the sign inside the root, it no longer follows the pattern of the product of a sum and a difference and the root terms will still be there after multiplication.

anonymous · Answer

Got it