$$ \\\\ {\\text{Given terminal point }}\\left( { - \\dfrac{{\\sqrt 3 }}{2}, - \\dfrac{1}{2}} \\right) \\\\ {\\text{Let angle be }}\\theta \\\\ \\Rightarrow \\sin \\theta = \\dfrac{P}{H} \\\\ \\Rightarrow \\sin \\theta = \\dfrac{1}{{2 \\times 1}} \\\\ \\Rightarrow \\theta = {\\sin ^{ - 1}}\\left( { - \\dfrac{1}{2}} \\right) \\\\ \\Rightarrow \\theta = \\left( { - \\dfrac{\\pi }{6}} \\right) \\\\ \\Rightarrow \\theta = \\pi - \\left( { - \\dfrac{\\pi }{6}} \\right) \\\\ \\Rightarrow \\theta = \\dfrac{{7\\pi }}{6} \\\\ $$ ","encodingFormat":"text/html"},"comment":{"@type":"Comment"}}]},{"@type":"Question","eduQuestionType":"Multiple choice","learningResourceType":"Practice problem","educationalLevel":"beginner","name":"Unit circle Quiz 1","text":" Find the terminal point of the unit circle at $$\\theta = 66^\\circ $$.","comment":{"@type":"Comment","text":" Apply $\\sin 66^\\circ = 0.9135$ and $\\cos 66^\\circ = 0.4067$ then further solve for coordinates."},"encodingFormat":"text/markdown","suggestedAnswer":[{"@type":"Answer","encodingFormat":"text/html","text":" $$\\left( {0,0.9135} \\right)$$","position":0},{"@type":"Answer","encodingFormat":"text/html","text":" $$\\left( {0.4067,0} \\right)$$","position":2},{"@type":"Answer","encodingFormat":"text/html","text":" $$\\left( { - 0.4067, - 0.9135} \\right)$$","position":3}],"acceptedAnswer":[{"@type":"Answer","encodingFormat":"text/html","text":" $$\\left( {0.4067,0.9135} \\right)$$","position":1,"answerExplanation":{"@type":"Comment","text":" $$ {\\text{Given angle is }66^\\circ } \\\\ {\\text{Let AOB is a triangle}} \\\\ {\\text{In }}AOB,{\\text{ AO is radius of }}1unit \\\\ \\Rightarrow \\sin 66^\\circ = \\dfrac{{AB}}{{AO}} \\\\ \\Rightarrow \\dfrac{{0.9135}}{1} = \\dfrac{{AB}}{1} \\\\ \\Rightarrow AB = 0.9135 \\\\ \\Rightarrow \\cos 66^\\circ = \\dfrac{{BO}}{{AO}} \\\\ \\Rightarrow \\dfrac{{0.4067}}{1} = \\dfrac{{BO}}{1} \\\\ \\Rightarrow BO = 0.4067 \\\\ \\therefore {\\text{ Terminal point is }}\\left( {0.4067,0.9135} \\right) \\\\ $$","encodingFormat":"text/html"},"comment":{"@type":"Comment"}}]},{"@type":"Question","eduQuestionType":"Multiple choice","learningResourceType":"Practice problem","educationalLevel":"beginner","name":"Unit circle Quiz 1","text":" Identity when the equation of the unit circle is a complex plane.","comment":{"@type":"Comment","text":" Apply $1 \\times 1$ valued unitary matrices for complex planes."},"encodingFormat":"text/markdown","suggestedAnswer":[{"@type":"Answer","encodingFormat":"text/html","text":" $${x^2} + {y^2} = 1$$","position":0},{"@type":"Answer","encodingFormat":"text/html","text":" $${x^2} - {y^2} = 1$$","position":1},{"@type":"Answer","encodingFormat":"text/html","text":" $$\\cos \\theta - i\\sin \\theta = \\cos \\theta$$","position":3}],"acceptedAnswer":[{"@type":"Answer","encodingFormat":"text/html","text":" $$\\cos \\theta + i\\sin \\theta = {e^{i\\theta }}$$","position":2,"answerExplanation":{"@type":"Comment","text":" The unit circle in the complex plane are the unit complex numbers $$ \\\\ T =\\{z \\in c:\\left| z \\right| = 1\\} \\\\ $$ The circle group forms a subgroup of $${c^x}$$, the multiplicative group of all non - zero complex numbers. $$ \\\\ $$ $$\\therefore {C^x}$$ is abelian $$ \\\\ $$ The circle group is also $$U\\left( 1 \\right)$$ of $$1 \\times 1$$ complex - valued unitary matrices $$ \\\\ $$ These act on the complex plane by rotation about the origin and parameterized the angle $$\\theta$$ $$ \\\\ \\therefore \\theta \\Rightarrow z = {e^{i\\theta }} = \\cos \\theta + i\\sin \\theta $$","encodingFormat":"text/html"},"comment":{"@type":"Comment"}}]},{"@type":"Question","eduQuestionType":"Multiple choice","learningResourceType":"Practice problem","educationalLevel":"beginner","name":"Unit circle Quiz 1","text":" If the equation of the unit circle is $${x^2} + {y^2} = {r^2}$$. What is the value of $$\\sec \\theta $$.","comment":{"@type":"Comment","text":" Apply $\\cos \\theta = \\dfrac{B}{H}$ then further solve the value of $\\sec \\theta $."},"encodingFormat":"text/markdown","suggestedAnswer":[{"@type":"Answer","encodingFormat":"text/html","text":" $$\\dfrac{x}{y}$$","position":0},{"@type":"Answer","encodingFormat":"text/html","text":" $$0$$","position":1},{"@type":"Answer","encodingFormat":"text/html","text":" $$ \\pm y$$","position":2}],"acceptedAnswer":[{"@type":"Answer","encodingFormat":"text/html","text":" $$ \\pm \\dfrac{1}{x}$$","position":3,"answerExplanation":{"@type":"Comment","text":"$$ \\\\ {\\text{Equation unit circle}} \\\\ \\Rightarrow {{\\text{x}}^2} + {y^2} = 1 \\\\ \\because {\\text{radius of unit circle is}} = 1 \\\\ \\Rightarrow \\cos \\theta = \\pm \\dfrac{B}{H} \\\\ \\Rightarrow \\cos \\theta = \\pm {x} \\\\ \\therefore \\sec \\theta = \\pm \\dfrac{1}{x} \\\\ $$","encodingFormat":"text/html"},"comment":{"@type":"Comment"}}]}]}