If m = (cos θ – sin θ) and n = (cos θ + sin θ) then show that

Given: m = (cos θ – sin θ)

n = (cos θ + sin θ)


Now, =


Multiply numerator and denominator by cos θ – sin θ :


Therefore, =


=


Now, =


Multiply numerator and denominator by cos θ + sin θ :


Therefore, =


=


Now, consider =


=


=


=


Divide numerator and denominator by cos θ:


=


=


Therefore, =


Hence, proved.


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