증명하는 방법?

# = L.H.S #

# = (1 + secx) / (tan ^ 2x) #

# = ((1 + 1 / cosx) / (sin ^ 2x / cos ^ 2x)) #

# = (cosx + 1) / cosx xxcos ^ 2x / sin ^ 2x #

# = ((cosx + 1) cosx) / sin ^ 2x #

# = ((cosx + 1) cosx) / ((1-cos ^ 2x)) #

# (취소 색 (청색) ((cosx + 1)) cosx) / (취소 색 (청색) ((1 + cosx)) (1-cosx)

# = cosx / (1-cosx) #

# = R.H.Scolor (녹색) (Proved.) #

대답:

아래 참조

설명:

# (1 + secx) / tan ^ 2x = cosx / (1-cosx) #

# (1 + secx) / (1-sec ^ 2x) = cosx / (1-cosx) #

# (1 + secx) / ((1 + secx) (1-secx)) = cosx / (1-cosx) #

# 1 / (1-secx) = cosx / (1-cosx) #

# 1 / (cosx / cosx-1 / cosx) = cosx / (1-cosx) #

# 1 / ((cosx-1) / cosx) = cosx / (1-cosx) #

# cosx / (1-cosx) = cosx / (1-cosx) #