A certain value in satisfies
Find .
Details
is fractional part function.
This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try
refreshing the page, (b) enabling javascript if it is disabled on your browser and,
finally, (c)
loading the
non-javascript version of this page
. We're sorry about the hassle.
L.H.S. = x 1 − [ x 1 ] = x 1 , since x lies between 2 , 3 , and its reciprocal is less than 1 .
R.H.S. = x 2 − [ x 2 ] . Now, 2 < x 2 < 3 ⇒ [ x 2 ] = 2
Therefore, simplifying we get x 2 x + 1 = x 2 . Adding and multiplying both sides by x , we get ( x + 1 ) 2 = x 2 ( x + 1 ) . Since x + 1 = 0 ⇒ x 2 − x − 1 = 0
Using the quadratic equation, we get x = 2 1 + 5 ,as the other root is discarded for being outside of the domain.
Thus, the value of P with x = 2 1 + 5 , is 5
Sorry if my solution is too brief.