<span> To get an explicit formula, we need to find an expression which gives the n-th term without having to compute earlier terms in the sequence. Looking at the numbers, and from the recursive formula, we see that the sequence is built by subtracting n from the previous term. This is similar to the triangular number sequence 1,3,6,10,15,... which has the explicit formula a_n = n(n+1)/2. In our case we are subtracting n from the previous term, so we multiply by -1/2 instead of 1/2. However, we also need to add a constant term to reproduce the numbers of the sequence. We can write a_1 = -1(2)/2 + c = 8. Therefore, c = 9.
So the explict formula is:
a_n = -n(n+1)/2 + 9</span>
The fact that the coefficients are pairwise identical (except for sign) tells you that x^2 -1 is a factor (and x-5 is the other factor). Of course, you recognize x^2-1 as a special form (the difference of squares) that is factored as (x +1)(x -1).
The zeros are x = -1, +1, +5.
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A graphing calculator confirms this.
Answer:4931520 yd
Step-by-step explanation:2,
802x1760=4931520yds
Answer:
7.527
Step-by-step explanation:
We know that 78% of the bar is gold and the total weight is 9.65 ounces. Just multiply the total weight by 78%.
9.65(0.78)= 7.527
