In the sequence {an}, A1 = 1, a (n + 1) = C * an + [n + 1 power of C * (2n + 1)], where the real number C is not equal to 0, then the general formula of an is?
This problem can be summarized according to the calculation results, and then proved by induction: A2 = C * a1 + [C ^ 2 * 3] = C + 3 * C ^ 2A3 = C * A2 + [C ^ 3 * 5] = C ^ 2 + 8 * C ^ 3A4 = C ^ 3 + 15C ^ 4A5 = C ^ 4 + 24C ^ 5 We can guess that an = C ^ (n-1) + (n ^ 2-1) * C ^ n. The following is proved by mathematical induction: when n = 1, the conclusion is true
I hope we can all be well?
I hope we will be find.
How much is 72 cents
72 points = 0.72 yuan
On the second power of the equation x + 2x = 3, this equation has a positive root and a negative root, right?
Yes, we don't need to find two. The sum of two is negative number - 2, and the product of two is positive number - 3. We can judge one positive and one negative
Fill in the blanks with proper forms of English words
Word given: damage; effect
1.The south of the country was worst ________ by the drought.
2.Smoking seriously ______ your health.
Why the first one uses effects and the second one uses images
The correct answer is as follows: 1) damage 2) effects / affected 2. Explanation: 1) damage refers to "damage / damage to objects", generally refers to the damage caused by natural disasters to places / roads / bridges, which can be repaired
SN is the sum of the first n terms of the arithmetic sequence. Given S6 = 36, Sn = 324, sn-6 = 144, then the value of n is?
This problem is too large, is there any simple? Did not write out the steps in detail. Forget
S6 = (a1 + A6) * 6 / 2 = 36, then a1 + A6 = 12 is expressed as 1
SN-S (n-6) = [a (N-5) + an] * 6 / 2 = 324-144 = 180, then a (N-5) + an = 60 is denoted as 2
And A6 + a (N-5) = a1 + an is denoted as 3
1. 2. By adding the two formulas and combining the three formulas, a1 + an = (12 + 60) / 2 = 36 is obtained
Sn = (a1 + an) * n / 2 = 324, so n = 324 * 2 / 36 = 18
Let X3 power y square + sin (XY) = x find the formula of DZ DZ. What I know is to push down almost,
x^3*y^2+sin(xy)=x
DZ?
Is there Z in the expression?
There seems to be a problem with the title, which is hard to answer
7 out of 11 minus 7 out of 11 multiplied by 7 out of 8
Extract 7 / 11 of the common factor, that is, 7 / 11 times 1 / 8 to get the solution
Tube formula 3.14/4 * (outer circle diameter square inner circle diameter Square) * length, the solution formula is to calculate what the tube, meaning
3.14/4 * (outer circle diameter square inner circle diameter Square) * length
=3.14 * (outer circle radius square inner circle radius Square) * length
=3.14 * outer circle radius square * length - 3.14 * inner circle radius square * length
=The volume of the cylinder filled with something in the middle - the volume of the middle gap
=Tube volume
For a function of two variables, the partial derivative exists, but it cannot be divided. Does this exist?
How can there be such a situation? Don't differential and derivative mean the same thing?
The partial derivative can only approach along the direction of the coordinate axis, while the differential can approach along two directions