Question

दिलेल्या अंकगणिती श्रेढीचे t10=20,t19=18 तर d=​

Answer 1

Answer:

bahini tuze uttar khalil parakare aahe

tyala brainliest tharav

ganitat especially bhumitit kinva sankhyiki mdhe kahi doubt asel mala vichaar

Step-by-step explanation:

so here for the given ap

t10=20 t19=18

so now using tn=a+(n-1)d

put n=10 first

so we get

t10=a+(10-1)d

ie a+9d=20 (1)

again applying same formula by putting n=19

we get

t19=a+(19-1)d

ie a+18d=18 (2)

so subtracting (1) from (2)

we get

9d=-2

ie d=-2/9

thus value of d is -2/9

Answer 2

Answer:

Step-by-step explanation:

t 10 =20, t 19 = 18

t10 = a+9d

a+9d=20...i

t19=18

a+18d=18...ii

Difference between EQ(I)and(ii)

a+9d-a-18d=20-18

-9d=2

d= -2/9