Evaluating Subscripts

Question

I need help with 2 equations for my College Algebra homework

I need to evaluate subscripts

1.) _[8]C_[4]

2.) _[7]P_[4]

Answer 1

Hey Lena,

There are several units of study where you would use subscripts. Two that come to mind immediately are Matrices and Sequences.

A matrix for emample 2 3 To identify the element 2, you would write n₁₁ . The first 1 identifies

6 8

what row the number is and the 2nd 1 idenfies what row it's in. To designate the 6, you would use the notation n_{21 .} The 2 idenfies that your number is in the 2nd row, the 1 lets you know it's in the 1st column. If that is your context, always remember it goes rows then columns (like RC cola) :)

You might also be in the unit where you are looking at patterns of numbers. Let's say I have the

sequence ....3, 6, 9....... I would say that the 3 is a₁ , the 6 is a₂ and the 9 is a₃. I could also go backwards and say the number before the 3 would be a _n-1 , the number before that would be a _n-2 and so forth.

Hope this helps.

Jetta McGinniss