Find an equation of a simple curved bridge support to go over the creek.
-條橋一定要有一個quadratic equation,而橋中間比人行個點要係個origin.
-top of the bridge support must be 5m above the flat ground level
-ends of the bridge support must span the creek which is 16m wide
and also what would be the equation of your bridge if the origin were moved to the left hand point where the bridge support meets the flat ground?
我知如果用y=a(x-p)²+q既equation..a 一定要係negative...但係點樣先可以和道到16m wide?
十分感謝可以解答到既朋友...唔該你們...
Quadratic Q(curved bridge)
2009-07-26 4:41 am
回答 (2)
2009-07-26 5:07 am
✔ 最佳答案
Let y=-a(x-α)(x-β) where a>0,β>αHowever, since the mid-point is at the origin, it means that β=-α
On the other hand β-α=16. Solve these equations, we get α=-8,β=8
and sub. x=0,we have -aαβ=5=>a=5/64
So y=f(x)=-(5/64)(x-8)(x+8)
if the origin were moved to the left hand point, then the equation becomes y'=f(x+8)=-(5/64)(x)(x+16)
2009-07-26 5:07 am
you meant ARCH BRIDGE?
收錄日期: 2021-04-26 13:44:43
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