5.5/5.6 (Nonright Triangles) Flashcards
What is the law of sines?
(a/sin A)=(b/sinB)=(c/sin C)
What is the law of cosines?
c^2=a^2+b^2-2ab sinC, where C is the largest angle
How do you find the area of a triangle given ASS? How many answers are there?
(1/2)ab sinC; 2 (even though the calculator will only give one)
How do you find area of a triangle given three sides?
Herons; s=(a+b+c)/2, k=/sqrt[s(s-a)(s-b)(s-c)]
What is the derivation of the Law of Sines?
Drawing an amplitude and equating sin of two angles.
What is the derivation for the Law of Cosines?
applying the distance formula from (a,0) to (x,y) but replacing the latter with (cCosB,cSinB)
How should you check the answer at the end of a Law of Sines question with two answers?
If two of the known angles add up to less than 180 degrees