- #1
fde645
- 50
- 1
Memorization, a contemptuous, futile, and insignificant method of learning math is, I think, not the solution to my problem. Well for the arithmetical progression, I have the formula:
Let: l= last term
a= first term
d= common difference
l= a+[d(n-1)]
And for the geometrical progression;
Let: l= last term
a= first term
r= common ratio
l= a(r^n-1)
and also,
for the getting the sum;
Let: l= last term
r= common ratio
a= first term
S= lr-a/ r-1
Now given these formulas, I have no idea how it is derived. I tried to formulate it on my own but I don't know how these equation was created. Please, give me tips to discern how a formula is made.
Let: l= last term
a= first term
d= common difference
l= a+[d(n-1)]
And for the geometrical progression;
Let: l= last term
a= first term
r= common ratio
l= a(r^n-1)
and also,
for the getting the sum;
Let: l= last term
r= common ratio
a= first term
S= lr-a/ r-1
Now given these formulas, I have no idea how it is derived. I tried to formulate it on my own but I don't know how these equation was created. Please, give me tips to discern how a formula is made.