Using the cosine
rule(c^2 =a^2 +b^2 −2abcosC), prove the
triangle inequality: if a,b and c are
sides of a triangle ABC, then a+b≥c
and explain when equality holds.
Further prove that sin α + sin β ≥
sin(α+β) for 0° ≤α,β≤180°
“MATHEMATICS”
CONTAINS
ALL THE LETTERS OF
“ETHICS”.
IS THERE ANY LESSON FOR US
IN ABOVE SAYING?
FOR “math-lovers”?
FOR “math-giants”?
FOR “overflow-mathematicians”?
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_( BTW this saying belongs to me)