Please answer this question from Introduction to trigonometry. if x = a tan θ and y = a sec θ, find the relation between x, y and a. About the author Sarah
Answer: [tex] {x}^{2} + {y}^{2} + {a}^{2} = 0[/tex] Step-by-step explanation: We have [tex]x = a \tan( \theta) \\ y = a \sec( \theta) [/tex] Squaring both equations, [tex] {x}^{2} = {a}^{2} \tan { \: }^{2} ( \theta) \\ {y}^{2} = {a}^{2} \sec { \: }^{2} ( \theta) [/tex] Adding both equations, [tex] {x}^{2} + {y}^{2} = {a}^{2} \tan {}^{2} ( \theta) + {a}^{2} \sec { }^{2} ( \theta) \\ {x}^{2} + {y}^{2} = {a}^{2} ( \tan {}^{2} ( \theta) + \sec {}^{2} ( \theta) )[/tex] Using [tex] \tan {}^{2} ( \theta) + \sec {}^{2} ( \theta) = – 1[/tex] [tex] {x}^{2} + {y}^{2} = {a}^{2} ( – 1) \\ {x}^{2} + {y}^{2} = – ( {a}^{2} ) \\ {x}^{2} + {y}^{2} + {a}^{2} = 0[/tex] Which is the required relation. Reply
Answer:
[tex] {x}^{2} + {y}^{2} + {a}^{2} = 0[/tex]
Step-by-step explanation:
We have
[tex]x = a \tan( \theta) \\ y = a \sec( \theta) [/tex]
Squaring both equations,
[tex] {x}^{2} = {a}^{2} \tan { \: }^{2} ( \theta) \\ {y}^{2} = {a}^{2} \sec { \: }^{2} ( \theta) [/tex]
Adding both equations,
[tex] {x}^{2} + {y}^{2} = {a}^{2} \tan {}^{2} ( \theta) + {a}^{2} \sec { }^{2} ( \theta) \\ {x}^{2} + {y}^{2} = {a}^{2} ( \tan {}^{2} ( \theta) + \sec {}^{2} ( \theta) )[/tex]
Using
[tex] \tan {}^{2} ( \theta) + \sec {}^{2} ( \theta) = – 1[/tex]
[tex] {x}^{2} + {y}^{2} = {a}^{2} ( – 1) \\ {x}^{2} + {y}^{2} = – ( {a}^{2} ) \\ {x}^{2} + {y}^{2} + {a}^{2} = 0[/tex]
Which is the required relation.