Inner Angle of an Triangle
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Hello, please look at the attached image. H and ang are given and I would like to calculate B
Moreover I need all angles from 0 to 180° at a fix H, lets assume H=6. and ang=0.5 ... 179.9.
How can I program this in matlab ? :-(
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Answers (3)
Torsten
on 31 Oct 2016
tan(ang/2) = (B/2) / H
thus
B = 2 * H * tan(ang/2)
Does that help ?
Best wishes
Torsten.
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Walter Roberson
on 31 Oct 2016
Divide into two right triangles and use trig. "Adjacent", or x, would be H, "opposite", or y, would be B/2, theta would be ang/2. By trig, x/y = tan(theta), so x / tan(theta) = y . Substiting back in, B/2 = H / tan(ang/2) and so B = 2 * H / tan(ang/2)
Now you can vectorize, B = 2 .* H ./ tan(ang./2) . ang can be a vector
Caution: tan() expects radians. You need to convert, or you need to use tand()
2 Comments
Torsten
on 31 Oct 2016
ang=1:1:179;
H=6.0;
B=2*H*tand(ang/2);
plot(ang,B);
Best wishes
Torsten.
Marv
on 31 Oct 2016
2 Comments
Torsten
on 31 Oct 2016
You mean B=12 for ang=90 and H=6 ?
That's what you get by the formula.
Best wishes
Torsten.
Walter Roberson
on 31 Oct 2016
Make sure you are using tand() instead of tan() if you are specifying the angle in degrees.
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