Question

a gp has its 3th and 7th terms as 45 and 3645 respectively.what is the product of the 2nd and third term (1)the sum of its seven term

Answer 1

Answer:

Step-by-step explanation:

Let first term be a and common ration

Atq,

a2=45

a7=3645.

Therefore, ar=45

a = 45 /r.....(I)

a *r to power 7-1 = 3645

Putting value of a=45/r in the above

45/ r * r to power 6 = 3645

45 * r to power 5 = 3645

r to power 5= 3645/45

r to power 5 = 81

Therefore, r = 5√81

r=3

Putting value of r =3 in eq. 1

a =45/r

a= 45/3

a =15

Product of second term and third term = a*r * a * r square

= 15 * 3 * 15 * 3 * 3

= 6075

Hope you can do forward .. thanks