Question:
What is the number of rational terms in the expansion of (31/2 +51/4)12?
What is the number of rational terms in the expansion of (31/2 +51/4)12?
Options:
- a) 2
- b) 3
- c) 4
- d) 6
- a) 2
- b) 3
- c) 4
- d) 6
correct answer : c)
Explanation:
Tr + 1 = n
r
rr
C 35
1
2
12 1
4() ()
–
= 12
12
2435C r
rr-
for rational term 12
2
– r and r
4 is integer.
\ Possible values of r = 0, 4, 8, 12
Tr + 1 = n
r
rr
C 35
1
2
12 1
4() ()
–
= 12
12
2435C r
rr-
for rational term 12
2
– r and r
4 is integer.
\ Possible values of r = 0, 4, 8, 12