Mudahkan ungkapan:? (sin ^ 2 (pi / 2 + alpha) -cos ^ 2 (alpha-pi / 2)) / (tg ^ 2 (pi / 2 + alpha) -ctg ^ 2 (alpha-pi /

2 (alpha-pi / 2)) / (tan ^ 2 (pi / 2 + alpha) -cot ^ 2 (alpha-pi / 2)

# = (sin ^ 2 (pi / 2 + alpha) -cos ^ 2 (pi / 2-alpha)) / (tan ^ 2 (pi / 2 + alpha)

# = (cos ^ 2 (alpha) -sin ^ 2 (alpha)) / (cot ^ 2 (alpha) -tan ^ 2 (alpha)) #

# = (cos ^ 2 (alpha) -sin ^ 2 (alpha)) / (cos ^ 2 (alpha) / sin ^ 2 (alpha) -sin ^ 2 (alpha) / cos ^ 2 (alpha)

# = (cos ^ 2 (alpha) -sin ^ 2 (alpha)) / ((cos ^ 4 (alpha) -sin ^ 4 (alpha)) / (sin ^ 2 (alpha) cos ^ #

# = (cos ^ 2 (alpha) -sin ^ 2 (alpha)) / (cos ^ 4 (alpha) -sin ^ 4 (alpha)) xx (sin ^ 2 (alpha) cos ^ #

# = (cos ^ 2 (alpha) -sin ^ 2 (alpha)) / ((cos ^ 2 (alpha) -sin ^ 2 (alpha) (sin ^ 2 (alpha) cos ^ 2 (alpha)) / 1 #

# = sin ^ 2 (alpha) cos ^ 2 (alpha) #