
Grade 12th passMagical Mathematics[Interesting Approach]
A repunit is a number that contains only the digit 1, and the repunit of n digits is denoted by
r(n)= 11111...1111 there are total n1
If f(x)=
90x2+20x2+1
then find the sum of digits of the number f(r(10))
A repunit is a number that contains only the digit 1, and the repunit of n digits is denoted by
r(n)= 11111...1111 there are total n1
If f(x)=
90x2+20x2+1
then find the sum of digits of the number f(r(10))




