SOLUTION: A reflecting telescope has a parabolic mirror for which the distance from the vertex to the focus is 26 feet. If the distance across the top of the mirror is 76 inches, how deep is
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Question 759712: A reflecting telescope has a parabolic mirror for which the distance from the vertex to the focus is 26 feet. If the distance across the top of the mirror is 76 inches, how deep is the mirror in the center? Answer by lwsshak3(11628) (Show Source):
You can put this solution on YOUR website! A reflecting telescope has a parabolic mirror for which the distance from the vertex to the focus is 26 feet. If the distance across the top of the mirror is 76 inches, how deep is the mirror in the center?
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place vertex at (0,0)
parabolic mirror opens upward:
equation of parabola: x^2=4py
p=26*12=312 inches
4p=1248
coordinates of right edge of mirror: (38,y)
x^2=4py
38^2=1248y
y=1444/1248≈1.1571
how deep is the mirror in the center? 1.1571 inches
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