The 4th term of an AP is zero.prove that its 25th term is triple its 1

1.	The 4th term of an AP is zero.prove that its 25th term is triple its 11th term.
Answer» 4th term is 0. i.e., a+3d=0therefore a=-3d25th term is a+24dputting the value of a in 25th term= -3d+24d= 21dand, 11th term is a+10d putting the value of a in 11th term= -3d+10d= 7d21d=3(7d)25th term = 3 of 11th termhence proved..... a+3d=0 a= -3d a25=a+24d=3(a11=a+10d)Put a=-3d-3d+24d=3(-3d+10d)21d=3(7d)21d=21d

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