November 9, 2018
#2070: Trig Identities explain
[Inside a single frame comic a right-angled triangle is shown. The shorter sides are labeled “a” and “b” and the hypotenuse has a “c”. All angles are marked: the right angle by a square and the two others by arcs. One arc (enclosed by “a” and “c”) is labeled by the Greek symbol theta (θ).]
[Supposed trigonometric functions of the marked angle θ are shown:]
sin θ = b/c
cos θ = a/c
tan θ = b/a
cot θ = a/b
sec θ = c/a
csc θ = c/b
cin θ = b/s
cas θ = o/c
tab θ = b²/na
bot θ = a/c → boat θ = a²/c → stoat θ = a²/c · st/b
tan θ ( = b/a = b/a · c/c = b/c · c/a = sin θ sec θ ) = insect θ²
(tan θ)² = b²/a² ( → t²n²a⁴ = b²/θ² → at²ba(na)² = b³/θ²
from physics: distance = 1/2 at² → ) distance2banana = b³/θ²
[Caption below the frame:]
Key trigonometric identities