Question Number 57621 by Gulay last updated on 08/Apr/19

Commented by Gulay last updated on 08/Apr/19

$$\mathrm{sir}\:\mathrm{help}\:\mathrm{me}\:\mathrm{plz} \\ $$
Answered by tanmay.chaudhury50@gmail.com last updated on 08/Apr/19
![S_9 =(9/2)[2a+(9−1)d] 72=(9/2)×2[a+4d] ((72)/9)=T_5 →T_5 =8 T_n =a+(n−1)d](https://www.tinkutara.com/question/Q57623.png)
$${S}_{\mathrm{9}} =\frac{\mathrm{9}}{\mathrm{2}}\left[\mathrm{2}{a}+\left(\mathrm{9}−\mathrm{1}\right){d}\right] \\ $$$$\mathrm{72}=\frac{\mathrm{9}}{\mathrm{2}}×\mathrm{2}\left[{a}+\mathrm{4}{d}\right] \\ $$$$ \\ $$$$\frac{\mathrm{72}}{\mathrm{9}}={T}_{\mathrm{5}} \rightarrow{T}_{\mathrm{5}} =\mathrm{8} \\ $$$${T}_{{n}} ={a}+\left({n}−\mathrm{1}\right){d} \\ $$