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`7+77+777+...777...7(n-"अंक")=7/81(10^(n+1)-9n-10)`

Sum to n term .7+.77+.777.......

Evaluate 7+ 77+777+...... upto n

Using mathematical induction show 7+77+777+......+n terms = 7/81(10^(n+1)-9n-10)

prove that 7 + 77 + 777 +...... + 777........._(n-digits) 7 = 7/81 (10^(n+1) - 9n - 10) for all n in N

prove that 7 + 77 + 777 +...... + 777........._(n-digits) 7 = 7/81 (10^(n+1) - 9n - 10) for all n in N

By using the Principle of Mathematical Induction, prove the following for all n in N : 7+77+777 +........ to n terms = 7/81 (10^(n+1)-9n-10) .

Evaluate 7+77+777+...... upto n

7, 77, 77, 777 div 77 equals

Sum to n terms the series 7+77+777+....