Question #f207b

2 Answers
Feb 12, 2018

Please see a Proof in the Explanation.

Explanation:

#secxcscx-cosxcscx#.

#=cscx(secx-cosx)#,

#=1/sinx{1/cosx-cosx}#,

#=1/sinx{(1-cos^2x)/cosx}#,

#=1/cancel(sinx){sin^cancel(2)x/cosx}#,

#=sinx/cosx#,

#=tanx," as desired!"#

Feb 12, 2018

See below

Explanation:

We will use the following identities:

#secx := 1/cosx#

#cscx := 1/sinx#

#tanx = sinx/cosx#

We now start the proof.

#secxcscx-cosxcscx#

#=1/(cos xsinx)-cosx/sinx#

#=1/(cosxsinx)-cos^2x/(cosxsinx)#

#=(1-cos^2x)/(cosxsinx)#

#=sin^2x/(cosxsinx)#

#=sinx/cosx#

#=tanx#, as required. #square#