Multiply both sides by <span>cos</span><span> </span><span>r<span>cos<span>(θ)</span></span>=<span>sec<span>(θ)</span></span><span>cos<span>(θ)</span></span>=1</span><span> </span><span>x=r<span>cos<span>(θ)</span></span></span><span> </span><span>x=1</span>
