If y = f(x) =(x+2)/(x-1) , then which of the following is correct ?
(a) x = f(y)
(b) f(1) = 3
(c) y increases with x for x<1
(d) f is a rational function of x
1y shouldnt [a] be the ans?
i mean y should this be a doubt...
i am having doubt by seeing this doubt :P
y is a decreasing function for all x..
and f(1) = infinity... not 3..
and since i dun have ne idea abt rational functions so d cant be corect :P
btw, wat are rational functions?
11y=x+2/x-1
subtract 1 from sides, [1]
y-1=3/x-1
x= 3/(y-1)+1
= y+2/y-1
= f(y)! [4]
1its a multiple correct answer question and i have doubt only in the last option......................
answer given is (a,d)
1skygirl:
wat are rational functions?
u know?
abhisheks.post:
rational fns??
skygirl:
yup
abhisheks.post:
i think fn of the form p/q
(x+1)/(x+2)
skygirl:
sure ?
abhisheks.post:
hmmmm
99%
skygirl:
okie :)
11Hey, x can still take irrational values. Then both numerator and denominator will be irrational.
Aman, the simplest solution for opt d being an answer is printing mistake [4]
33No it doesnot give rational values but is called rational function.... as it is in the form of p/q
don't ask why........... it is its name...
1priyam if rational function is of the form p/q, then there is a condition that p&q must be integers.....