third term of an AP is p and fourth term of the AP is q find the tenth and the general term

Any nth term of an AP with first no as 'a' and common difference 'd' is given by an = a + (n-1)d

Thus difference between 3rd and 4th term = common difference = d =a4-a3 = q-p

Now a3  = a + (3-1)(q-p)  = p

a+ 2q- 2p =p 

a= 3p-2q

Thus nth term  = (3p-2q) + (n-1) (q-p)

Also 10th term = 3p-2q + 9(q-p) = 7q-6p

  • 10

t3=p; t4=q

t4-t3=d=q-p

t1=t4-3d=q-3[q-p]=3p-2q

tenth term=t1+9d=3p-2q+9[q-p]

t10=3p-2q+9q-9p=7q-6p

  • -3
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