Problema Solution
Use the 45-45-90 Triangle Theorem to find the sine and cosine of a 45 degree angle.
Answer provided by our tutors
Consider thriangle ABC, angleB=90° and angleA&angleC=45°
AB=BC and AC is the hypotenous.
Let AB=1 unit
hence BC=1
hence AC2=AB2+BC2 using pythagoras theorem.
hence AC2= 1+1
AC=Sqrt(2)
sin angleA=opposite side/hypotenous
sin 45° = BC/AC =1/sqrt(2)
cosangleA=adjacent side / hypotenious
cos 45° =AB /AC =1/sqrt(2)