If a and b are the unit vector then prove that |a-b|=1/2 SinA

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If the ratio of sum of the first m and n terms of an ap is m2 : n2 , show that the ratio of its mth and nth terms is (2m − 1) : (2n − 1).

To prove that angle def = angle dgf by sas, what additional information is needed? def congruent to dgf dfe congruent to dfg de congruent to dg dg congruent to gf

Ratio of circumference to diameter example plz i need to now what it looks like.