Let Tr be the rth term of an A.P., for r=1,2,... If for some positive integers m and n,Tm=1n;Tn=1m then find Tmn.
A
1mn
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
1m+1n
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
1
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
0
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution
The correct option is D1 Tm=1n (given) a+(m−1)d=1n⟶1 Tn=1m (given) a+(n−1)d=1m⟶2 Substract equation 2 from 1, we get (m−1)d−(n−1)d=1n−1m d[m−1−n+1]=m−nmn d[m−n]=m−nmn d=1mn⟶3 Put value of d in equation 1 a+(m−1)1mn=1n amn+(m−1)mn=1n amn+m−1=m a=1mn⟶4 Tmn=a+(mn−1)d Tmn=1mn+(mn−1)1mn (From equation 3 & 4) Tmn=1+mn−1mn=mnmn Tmn=1