How can excel quickly classify ABCD in order of AA BB CC DD? Using Excel to sort~ For example: Data a: 123456 B：645679 C：456464 A：123455 B：668877 C：321457 . How to arrange for A: A: . B: B: . C: C: . This format. Please be more detailed

How can excel quickly classify ABCD in order of AA BB CC DD? Using Excel to sort~ For example: Data a: 123456 B：645679 C：456464 A：123455 B：668877 C：321457 . How to arrange for A: A: . B: B: . C: C: . This format. Please be more detailed

Suppose the data is like this: the data of cell A1 is: "A: 123456", A2, A3. An analogy is the data above you
You can do this:
Enter the formula in B1: = left (a1,1), and then select b1 to fill down. After filling, select column B
Ascending or descending order --- sort method: expand to the selection area (this is the key)
In this way, it can be arranged according to aabbccdd, and then you can delete the auxiliary formula of column B

As shown in the figure, the straight line L passes through a vertex a, DD '⊥ LBB' ⊥ L, CC '⊥ l of the parallelogram ABCD, the perpendicular feet are D1, B1, C1, and the metric line segments CC1, dd1, BB1, to explore the relationship between them and explain the reason

CC1=DD1+BB1.
It is proved that if AC and BD are connected at point O, then Bo = OD, Ao = OC. Make oo1 perpendicular to O1
If BB1, CC1 and dd1 are perpendicular to L, then BB1, oo1, CC1 and dd1 are parallel to each other
So: b1o1 / o1d1 = Bo / OD = 1, b1o1 = o1d1;
Similarly, AO1 = o1c1
Oo1 is the median line of ⊿ acc1 and oo1 is the median line of trapezoidal b1bdd1
Then: CC1 = 2OO1; dd1 + BB1 = 2OO1
Therefore, CC1 = dd1 + BB1

The four vertices a, B, C and D of planar quadrilateral ABCD are all outside the plane a determined by parallelogram A1, B1, C1 and D1, and Aa1, BB1, CC1 and dd1 are parallel to each other

It is proved that: ∵ Aa1 ‖ CC1, A1B1 ‖ c1d1, Aa1, A1B1 ⊂ plane aa1b1b, CC1, c1d1 ⊂ plane cc1d1d1d, Aa1 ∩ A1B1 = A1, ∩ plane aa1b1b ‖ plane cc1d1d, and by plane ABCD ∩ plane aa1b1b = AB, plane ABCD ∩ plane cc1d1d1d = CD, so ab ‖ CD, the same as ad ‖ BC, so ABCD is a planar quadrilateral

It is known that e is a point on edge A1B1 of cube abcd-a1b1c1d1, and the cosine value of the angle between the out of plane straight line AE and BC1 is (3 √ 5) / 10
(1) Find the size of dihedral angle e-bc1-b1
(2) Find the angle between AE and bec1
Ask for detailed explanation

1. Connect ad ', let edge length be 1 ∵ ad' ∥ BC '∥ d'ae, which is the angle formed by AE and BC', cos ∥ d'ae = (ad '&# 178; + AE & # 178; - d'e & # 178;) / (2ad' · AE) = ad '/ 2ae = 3 √ 5 / 10ad' = √ 2 ∥ AE = √ 10 / 3a'e = 1 / 3 b'e = 2 / 3, connect b'c with BC 'in F, then BC' ⊥ b'f BC '⊥ EB' ⊥ BC '⊥ EF ⊥ E