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stupidinmath
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I'm quite confused. i dont know now T.T arc length: l = 2(theta)(r)(theta/360) l = 2(90)(5)(90/360) l=225 225x4 = 900 perimeter is 900cm
arc length : \(\large l = 2 (\theta)r \frac{\pi}{360}\) now try
oh, wrong formula. ok let me solve it:)
This is just a thought, but wouldn't the perimeter of the shaded region be equal to the circumference of a circle with a radius of 5 cm?
Or, you can see that there are four quarter arcs of radius 5 which give u 1 complete perimeter of circle of radius 5
my arc length is 7.85 so.. my perimeter of the shaded region is 31.42 approximately. is that right?
\(\large \color{red}{\checkmark}\) next try if you get lncognlto's suggestion...
ah, yes, thanks. and yup, what he said was right:) I just need a complete solution though:) thanks guys
both methods are considered complete solutions :) u wlc :) however ur teacher wud get more impressed if u do the lncognlto's method...
oh, haha, alright, will do that :)
@ganeshie8 , if this is the problem.. would the formula still be 2(theta)(r)(pi/360) or it should be 2(theta)(2)(pi/180)?
Alright, here is the original formula :- arc length \(l = r\theta\) \(\theta\) is in radians
to convert given \(\theta\) degrees into \(\theta\) radians, u multiply \(\frac{2\pi}{360}\) which is same as multiplying \(\frac{\pi}{180}\) :- arc length \(l = r \theta \frac{2\pi}{360}\) \(\theta\) is in degrees now
for the triangle, did they give u any dimensions ?
thank you so much. yep, ill post my solution later for checking:)
May I give another thought? xD
If this triangle is equilateral, then the angles of each of the sectors is going to be 60 degrees. Thus three sectors together make 180 degrees, or half a circle. So the perimeter of the shaded region would then be equal to half the circumference of a circle with the radius equaling half the length of a side of the triangle.
oh, that's right. smart one. Hahaha. will remember that:)
60 + 60 + 60 and 180 which one save u time ha ? I'm sure ur teacher wants u do this exactly as lcognlto suggests !
i believe so too:)