Find the mathematical formula derived from the following numbers

The first group: an=(a1-1)+1, an represents the nth number you request, a1=1, a2=2, and so on.

The second group: an=an-1+5*(n+1), where a0=0 and an-1 represents the previous number of an.

I hope it's correct, I haven't used high school math for a long time, and I'm rusty.

Each term is the sum of the difference series, the first term is 10, the difference is 5, so the sum is 10n+n(n-1) 2*5, the wealth you give is too little, add some wealth.

an=an=5 2+5 3+5 4+5 5+......5×(n+1)

Simplification can be obtained.

The number in the second row = 5 x [(n+n 2) 2+n] [The previous one was written incorrectly, this is right.] 】

This can remind you that the difference in the results is basically a multiple of 5.

This is calculated using the logarithmic operation formula, and you can do the math yourself. Be sure to grasp the relevant formulas and calculate carefully.

g'(x)=0

a^xlna=－b^xlnb

lna lnb= b x a x= (b a) x and logarithm on both sides to get x

According to the line chart of electronic **, which is approximate to the parabola, then it is done according to the parabola, set a quadratic function, substitute it with three sets of values, and get an approximate parabolic analytic formula, but it can only be regarded as an approximate formula:

This formula is effective and absolutely accurate, but it is computationally intensive.

Well, I know this algorithm just hasn't worked for a long time and I don't know how to write a formula for you. Or I'll give you my algorithm and write your own formula.

The width and height of the three cuboids are the same, but the length is different. Calculate the volume according to the volume of the box = length, width and height, and then add it up:

7×15×26+40×15×26+7×15×26=20280(cm³)

Think of this bag as a cuboid, volume = base area height = length width height.

v=sh=abh

Find the length, width and height of each one, and then use Length * Width * Height to get the volume of each box.

The sum of the three is the total bag volume.

Subtract the first term from the second term, or divide the second term by the first term to see if it is a fixed value, if it is dust, it is equal to the buried difference or the proportional number series is bent and destroyed, if not, it may be mixed with the difference and how the ratio is mixed.

=x*(x+1)/2

The average value is (x+1) 2, a total of x, so =x*(x+1) 2

n+[n*(n-1)] 2 is the formula. This is the formula for summing the series of equal differences. This is the formula for a difference of 1.

The formula for the difference series is: na1+ 2}d

What kind of eye does it take to see this ...

1 All assume 5 trainings:

The composition of 1 and 5 is 10%, 15%, 20%, 25%, 30% E1 The effectiveness of E5 is 80, 90, 60, 85, 100e=10%*80+15%*90+20%*60+25%*85+30%*100=