PS - Setting Q

Question

1/(4-15^1/2) ?

SimaQ · Answer

Simple but a bit tricky aswell...
Not sure if this is correct.

1/(4-sqrt15).....raise each figure individaully to the power of 2

1/(16-15)=1....

Answer 1

anandsebastin · Answer

I am not sure that your methodology is correct, Sima. If you think about it, the square root of 15 will be close to 4. So, the difference will be less than 1, resulting in an answer that is greater than 1. 

15^1/2 ~ 3.9. So, somewhere between 5-10 would be the answer
It would be easier if the choices were posted.

jaynayak · Answer

1/(4-sqr(15)) 

= 4+sqr(15) / 16-15

= 4 + sqr(15) 

Now sqr(15) ~ > 3.5

Hence the answer should be ~ 8

girikorat · Answer

1/(4-15^1/2) = (4+15^1/2)/ 

= (4+15^1/2)/16-15 
= (4+15^1/2)
= 7.873
= 8 (Rounding off)

Matrix02 · Answer

Tricky one:

1/(4-15^1/2) = 

1/4-sqrt15 =

multiple denominator and numerator by 4+sqrt15

1(4+sqrt 15)/(4- sqrt 15)*(4+sqrt 15) =

4+sqrt 15/1 = 

4+ sqrt 15 ~ 4+3.87 = 7.87ish

PS - Setting Q

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