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In the same circle, arc AB is equal to twice arc CD, then the relationship between chord AB and CD is In the same circle, arc AB is equal to arc CD, then the relationship between chord AB and CD is A. AB > 2x CD B. AB equals 2x CD C. AB less than 2x CD D. Unable to determine
C
Let e be the midpoint of arc AB, then arc AE = arc be = arc CD
Even AE, be, ab
AE = be = CD
AE + be > AB (both sides of triangle and > third side)
2AE>AB
AE>AB/2
CD=AE>AB/2
Calculate the unfolding length of steel plate and circular pipe as shown in the figure below. Please explain in detail. It is best to have a formula
Take the length of central axis
This is the blanking length
It's simple
The calculation formula of the total length after expanding around the circle! The calculation formula of the total length after expanding around the circle! There is a part, like a roll of adhesive tape, which starts from the inside and turns outward. The number of turns can be counted and the thickness can be measured to find the calculation formula of the total length (because the part cannot be disassembled, otherwise it will be simple)
Measure the diameter D of the innermost circle (the first circle) and the diameter D of the outermost circle, and count the number of turns n
Perimeter of the first circle: π D
Perimeter of circle X: π [D + (D-D) * (x-1) / (n-1)]
Total length = n π D + n π (D-D) / 2
Is the arc length the length of the arc expansion? What is the calculation formula?
Arc length is the length of arc expansion. The calculation formula is generally as follows: arc length L = R ×θ (here) θ It refers to the angle corresponding to the arc. The unit is radian, which is generally recorded as RAD)
How to calculate the expanded length of a circle The existing cylinder with a diameter of 2600mm is 1500mm high. How to calculate the length of the cylinder when it is unfolded, that is, how long circular plate can be used to roll up the cylinder with a diameter of 2600mm? Suppose it is a 10mm thick iron plate, how to add allowance?
3. 14 * 2600mm = 8164mm, i.e. 8164mm * 1500mm rectangular plate. Note: 8164mm is clean. It depends on what material you use, and appropriate allowance should be added
The derivation process of the formula for judging the length of the string cut by a straight line by algebraic method |AB|=√(1+k^2)|x_ 1-x_ 2| =√{(1+k^2)[(x_1+x_2)^2-4x_1x_2]} It's a formula The distance formula between two points should not be | P_ 1 P_ 2 = √ [(x_1-x_2) ^ 2 + (y_1-y_2) ^ 2]. How to deduce | AB = √ (1 + K ^ 2) | x_ 1-x_ 2 | yes? I think the chord length should be √ [(x_1-x_2) ^ 2 = (kx_1-kx_2) ^ 2] (where x_1 and x_2 are the abscissa of the two intersections respectively, and y_1 and y_2 are the ordinates of the two intersections respectively
AB
=√ [(x1-x2) ^ 2 + (y1-y2) ^ 2]. This is the two-point distance formula
(x1, Y1), (X2, Y2) is on the line y = KX + B
∴y1=kx1+b
y2=kx2+b
Simplification of distance formula
=√[(x1-x2)^2+k^2(x1-x2)^2]
=√[(1+k^2)(x1-x2)^2]
=√(1+k^2)|x1-x2|
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