Verify? #2cosx-secx=cosx-tanx/cscx#

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Answer 1 · 2017-03-29T04:42:06

See below:

#2cosx-secx=cosx-tanx/cscx#

#2cosx-1/cosx=cosx-(sinx/cosx)/(1/sinx)#

#2cosx-1/cosx=cosx-(sinx/cosx)xx(sinx)#

#2cosx-1/cosx=cosx-sin^2x/cosx#

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

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

Use #color(blue)(sin^2x+cos^2x=1)=>color(red)(sin^2x=1-cos^2x#

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

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

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