Question

please help me ...
plz solve this question...​

Answer 1

Answer:

p = 21  & a(11) = 0

Step-by-step explanation:

Given,  Sum(q terms) = 63q - 3q²

S(1) = 63 * 1 - 3* 1²

=60 = a1 {sum of first 1 term is first term }

S2 = 63 * 2 - 3* 2²

     =114

S2 - S1 = 114 - 60

=> 54 = a2 {2nd term => Sum of first two terms - sum of first term}

SO , d = a2 - a1 => 54 - 60 = - 6

Now,

pth term = - 60

= a1 + (p-1) d = - 60

= 60 + ( p-1) -6= - 60

= p-1 = -60-60 / -6

= p = 21

Now,

a11 = a1 + 10 d

=> 60 + 10 *(-6)

=>  60 + (-60)

=>  0