Progressions

A sequence where each term after

A sequence where each term after the first is obtained by adding a fixed number (common difference 'd') to the preceding term. General form: a, a+d, a

The constant value added to each

The constant value added to each term to get the next term in an A.P. It can be positive, negative, or zero. Found by subtracting any term from the su

Two formulas

Two formulas: Sn = n/2[2a + (n-1)d] when first term and common difference are known, or Sn = n/2(a + l) when first and last terms are known, where l i

A sequence where each term after

A sequence where each term after the first is obtained by multiplying the preceding term by a fixed non-zero number called common ratio 'r'. General f

The constant factor by which each

The constant factor by which each term is multiplied to get the next term in G.P. Found by dividing any term by the preceding term: r = ak+1/ak where