If sum of n terms of Ap is given by 3n2+5n then find the common diffrence and the 25th term
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sn=3n^2+5n
s1=a1=3(1)^2+5(1)=8
s2=3(2)^2+5(2)=22
s2=22=a1+a2
a2=228=14
d=a2-a1=14-8=6
25th term =a+(n-1)d
25th term =8+(25-1)6
25th term =8+144
25th term =152
s1=a1=3(1)^2+5(1)=8
s2=3(2)^2+5(2)=22
s2=22=a1+a2
a2=228=14
d=a2-a1=14-8=6
25th term =a+(n-1)d
25th term =8+(25-1)6
25th term =8+144
25th term =152
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