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PA is perpendicular to the plane of the square ABCD with side length a, PA = a, then the size of the dihedral angle b-pc-d is It needs a rough process
Make PC vertical BN through B, and calculate BN = ((√ 6) / 3) a from the length of side. Then calculate PD = √ 2A So DN is vertical to PC, the plane angle of dihedral angle b-pc-d is angle Bnd. Connect BD, and BD = √ 2A
According to cosine theorem, cosbnd = (BN ^ 2 + DN ^ 2-bd ^ 2) / 2bn × DN = - 1 / 2
So the angle Bnd is equal to 120 degrees
RELATED INFORMATIONS
- 1. Through the vertex a of the square ABCD, make the line PA ⊥ plane ABC, and PA = Pb, then the degree of the sharp dihedral angle formed by plane ABC and plane PCD is? Sorry, wrong number. It's not pa = Pb, it's PA = ab
- 2. Given that PA ⊥ square ABCD, if AB = PA, then the dihedral angle of plane PAB and plane PCD is
- 3. If the line AP is perpendicular to the plane ABCD through the vertex a of the square ABCD, and AP = AB, then what is the dihedral angle between the plane ABP and the plane CDP? (Figure)
- 4. If the vertex a of the square ABCD passes through the AP vertical plane ABCD and AP = AB, then the degree of the dihedral angle between the plane ABP and the plane DCP is Draw a picture
- 5. If the vertex a of the square ABCD passes through the line AP ⊥ plane ABCD, and AP = AB, then the degree of the dihedral angle formed by the plane ABP and the plane CDP is If you do well, you can pay me a picture, because I don't know how to draw a plane CDP
- 6. Through the vertex a of square ABCD, do PA ⊥ plane ABCD, PA = AB = 1, find the dihedral angle formed by plane APB and plane cpd
- 7. Given that ABCD is a rectangle, ab = a, ad = B, PA ⊥ plane ABC, PA = C, then the distance from point P to BC and BD is How to find two distances?
- 8. Given that ABCD is a rectangle, ab = a, ad = B, PA ⊥ plane ABC, PA = C, then the distance from P to BC is? And the distance from P to BD is?
- 9. Given that PA is perpendicular to the plane of rectangle ABCD, and ab = a, ad = B, PA = 2c, find the distance from the midpoint Q of PA to the straight line BD
- 10. PA is perpendicular to the plane of rectangle ABCD, and ab = 3cm, ad = 4cm, PA = 6 / 5 root 21cm. Calculate the distance from point P to BC and BD respectively
- 11. If the bottom of p-abcd is a parallelogram, the bottom of PA ⊥ is ABCD, the point E is on the side edge PC, and PE = 13pc, then VP − bdevp − ABCD=______ ．
- 12. The bottom of p-abcd is a parallelogram, the bottom of PA ⊥ is ABCD, e is a point on PA, and the section of PC ∥ is BDE Find the volume ratio of the two parts of the pyramid p-abcd divided by the section BDE
- 13. The bottom surface of the pyramid p-abcd is a square with side length 1, and the side edge PA is perpendicular to the bottom surface ABCD. Moreover, PA = 2. If e is the midpoint of PA, we prove the plane BDE
- 14. P is a point outside the parallelogram ABCD, and Q is the midpoint of PA
- 15. P is a point out of the plane of the parallelogram ABCD. Find a point E on PC to make the PA ‖ face be, and give the proof
- 16. P is the point out of the plane of the parallelogram ABCD, and Q is the midpoint of PA
- 17. P is a point outside the parallelogram ABCD, and Q is the midpoint of PA
- 18. Let p be a point in the square ABCD, and the distances from point P to vertex ABC are 1, 2 and 3 respectively
- 19. P is a point inside the square ABCD. The distances from point P to vertex a, B and C are 1, 2 and 3 respectively. Find the side length of the square Using trigonometric function solution, there are two results under the solution. Why should 5-2 √ 2 be omitted?
- 20. A mathematical problem: let p be a point inside the square ABCD, and the distances from P to vertex a, B and C are 1, 2 and 3, respectively