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Ask a math problem with nine tricks.
Solution: Judging from the meaning of the problem,

The vertex of the cone is s,

Point A is any point on the intersection of the bottom and side of the cone.

If the cone is cut along the generatrix SA, it will become fan-shaped after expansion.

The relationship before and after expansion is:

The radius of the expanded sector is the generatrix of the original cone;

The arc length of the expanded sector is the bottom circumference of the original cone.

The radius of the base of the original cone is 1.

∴ The circumference of the base of the original cone is 2××××1= 2 π.

∴ The arc length of the expanded sector is 2π.

* The bus length of the original cone is 4.

The radius of the extended sector is 4.

∴ The circumference of the circle where the expanded sector is located is: 2×π×4=8π.

Only the arc length of the expanded sector is found to be 2π.

∫(2π)/(8π)= 1/4, that is, 2π accounts for 8π 1/4.

The arc length of the expanded sector is equal to 65438+ 0/4 of the circumference of the expanded sector.

∴ The central angle of the expanded sector is equal to 0/4 of 65438+360,

The central angle of the expanded sector is equal to 90 degrees.

Even communication, it is in the delta capsule.

∠ASC = 90,SA = 4,SC = ( 1/2)× 4 = 2

∴: Line segment AC = 2√5 obtained from Pythagorean theorem.

The line segment AC is the shortest distance for insects to crawl, and the shortest distance is 2√5.

Good luck with your study!