An easy way to remember the trigonometric ratios in right angled
triangles:
Let opposite side be “t”
Let hypotenuse side be “s”
Let adjacent side be “a”
#Sin theta =(opposite)/ ( hypotenuse) = t/s = Sin(ts)#
#Cos theta = (adjacent ) /( hypotenuse ) = a/s = Cos(as)#
#Tan theta = (opposite)/(adjacent) = t/a = Tan(ta)#
#Cosec theta = (hypotenuse)/(adjacent) = s/t = Cosec(st)#
#Sec theta = (hypotenuse)/(adjacent) = s/a = Sec(sa)#
#Cot theta = (adjacent)/(opposite) = a/t = Cot(at)#
#180° -(70° 49'15.6''+90°)=19°10'44.4''= angleB#
#s/a = Sec 19°10'44.4''#
Multiply both sides by a
#s = Sec 19°10'44.4'' xx a#
#s= 1.058764789 xx 23#
#s = 24.352# = hypotenuse = side b#
Check:
#t/s = Sin 19°10'44.4'' #
Multiply both sides by s
#t= Sin 19°10'44.4'' xx s#
#t = 0.328520492 xx 24.352 #
#t = 8# = opposite side = b#