Question

Find the no. In ap whose sum is 21 and product is 315

Answer 1

Answer:

Step-by-step explanation:

according to question ..

(a+a+d)=21 ;         *equation 1 ;

(a*(a+d))=315 ;      *equation 2;

so

from equation 1 ;

2*a+d=21 ;

d=21-2*a ;

now putting the value of d in equation 2 ;

(a*(a+21-2*a))=315 ;

(a*(21-a))=315 ;

21*a-a*a=315 ;

a*a-21*a+315 =0 ;

remark == use quadratic equation you will find imaginary roots and put it in equation 1 or 2 to get value of d ;