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ssssasssahl
Then press these to expand to the face.
The others are parallel, perpendicular.
Just get the vector ones right.
There are books on it... You're a tutor.
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Congruence, similar knowledge should be used, and some properties of the circle will also be often used, such as the diameter of the circle is a right angle to the circumferential angle, the corresponding line segment of the parallel line cut is proportional, and the properties of the parallelogram will be commonly used.
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All the formulas for high school solid geometry are as follows:
1. Cube a-side length s=6a2; v=a3。
2. Cuboid a-long; b-wide; c-high; s=2(ab+ac+bc);v=abc。
3. Cylindrical r-bottom radius; h-high; c—circumference of the bottom surface; S bottom - bottom area; S side — side area. S surface - surface area is noisy, c = 2 r, s bottom = r2, s side = ch, s table = ch + 2s bottom, v = s bottom h = r2h.
4. Hollow cylinder r-outer radius; r-inner circle radius; h-high; v=πh(r2-r2)。
5. Straight cone r-bottom radius; h-high v = r2h3.
6. Round table r - upper bottom radius r - lower bottom radius h - high, v= h(r2+rr+r2) 3.
7. Prismatic S-bottom area; h-high; v=sh。
8. Pyramid S-bottom area h-high; v=sh/3。
9. The upper and lower bottom areas of the prism S1 and S2 are h-high; v=h[s1+s2+(s1s1)1/2]/3。
10. Pseudo-cylinder S1-upper and bottom area; s2-lower bottom area; s0-mid-sectional area; h-high; v=h(s1+s2+4s0)/6。
11. a ball r-radius; d - diameter, v = 4 3 r3 = d2 6.
12. Ball lack H-ball lack high; r-ball radius; a-radius of the ball missing the bottom, v= h(3a2+h2) 6= h2(3r-h) 3, a2=h(2r-h).
13. The ball table R1 and the lifting and cleaning die R2 - the upper and lower bottom radius of the ball table; H-high, v = h[3(r12+r22)+h2]6.
14. a toroidal r-torus radius; d-Ring diameter; r-torus cross-sectional radius; D-Ring cross-section forward diameter v=2 2rr2= 2dd2 4.
15. Barrel body D-barrel belly diameter; d-Diameter of the bottom of the barrel; H - barrel height, v = h (2d2 + d2) 12 (the bus bar is arc-shaped, the center of the circle is the center of the barrel) v = h(2d2 + dd + 3d2 4) 15 (the bus bar is parabolic).
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Cube incision sphere r=a 2;Outside ball r=a 3 2;Ridge catchr = a 2 2;
Regular tetrahedral incision ball r=a 6 12;Outside ball r=a 6 4;Ridge catches r=a 2 4;
Quadrangular pyramid inscribed ball r=a( 6- 2) 4;Outside ball r=a 2 2;Ridge catches r=a 2;
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1) Incut Ball:
The inscribed ball is tangent to all sides of the cube, so radius r=a 22) outward catch:
The vertices of the cube are on the outside ball, and the diagonal length of the cube is 2r, r=(root number 3)a 2
The edge catches the ball through the midpoint of the cube, and the face angle of the cube is 2r long, r = (root number 2) a 2
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ab should be the diameter.
acb=90°
PO Bottom ABC
po⊥abpa=pb=6
ao=ob=4
po=2√5
Connect to the OMOM PB
om=1/2pb=3
The magnitude of the angle formed by the radius OC and the bus PB is equal to 60°, i.e. MOC = 60°
Cosine theorem.
cos60°=(om +oc -cm) (2*om*oc) to get cm= 13
Over m as mn ab in n
ab//po
Mn = 5, the angle formed by the heterogeneous straight line MC and Po, i.e., cmn
cos cmn=mn cm= 5 13= 65 13 The angle formed by the heterogeneous straight line MC and PO = arccos 65 13 If you agree with my answer, please click "Accept as satisfactory answer" in the lower left corner, and wish you progress in learning!
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What does ab and oc mean when they are the radius of the base circle, and what is the center of the bottom circle?
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