The sine and cosine rule Used in finding the angles and lengths of sides of triangles provided that some information is provided for triangles that are not right angled triangles. Both are usually stated using a standard labelling of the triangle.
The sine rule (a/sinA=b/sinB=c/sinC) is used to find a missing angle or length, and may be used if other lengths and angles of the triangle are known.
The sine rule can result in non-unique, or more than one, solutions for a given set of data. this concept is called the ambiguous case. The ambiguous case will be used when two of the angles of a triangle are not given
The law of cosines is usually applied to triangles in which the pairing of an angleandthe opposite side. The cosine rule is generally more complicated. The cosine rule:
a^2=b^2+c^2-2bcCosA
b^2=a^2+c^2-2acCosB
c^2=a^2+b^2-2abCosC
The cosine rule can be remembered as a version of pythagorean Theorem with a correction factor Graphs and properties of the sine and cosine functions include f(x)=asinx + c
f(x)=acosx + c
f(x)=sinbx + c
f(x)=acosbx + c
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