Given : $$tan^2θ + cot^2θ = 2$$
=> $$tan^2θ + cot^2θ - 2=0$$
=> $$tan^2\theta+cot^2\theta-2(tan\theta)(cot\theta)=0$$ [$$\because tan\theta cot\theta=1$$]
=> $$(tan\theta-cot\theta)^2=0$$
=> $$tan\theta-cot\theta=0$$
=> $$tan\theta=cot\theta$$
=> $$tan\theta=tan(90^\circ-\theta)$$
=> $$\theta=90^\circ-\theta$$
=> $$\theta+\theta=2\theta=90^\circ$$
=> $$\theta=\frac{90}{2}=45^\circ$$
$$\therefore$$ $$2sec\theta-cosec\theta$$
= $$2sec(45^\circ)-cosec(45^\circ)$$
= $$2\sqrt2-\sqrt2=\sqrt2$$
=> Ans - (D)
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