Math, asked by sayedaakef, 10 months ago

if tan theta equals to 1 then find the values of sin theta + cos theta upon sec theta + cosec theta​

Answers

Answered by Anonymous
5

tan \theta \: = 1 = tan45 \degree \\  \therefore \:   \fbox{\theta = 45 \degree} \\  \\ so \\  \\ sin \theta = sin45 =  \frac{1}{ \sqrt{2} }  \\  \\ cosec 45=  \frac{1}{sin45}  =   \sqrt{2}  \\  \\and.......  \\  \\ cos45 =  \frac{1}{ \sqrt{2} }  \\  \\ sec45 =  \frac{1}{cos45}  =  \sqrt{2}

Answered by varadad25
49

Question:

If \tan\:=\:\sf\:1, then find the value of \sf\:\dfrac{\sin\:\theta\:+\:\cos\:\theta}{\sec\:\theta\:+\:\csc\:\theta}

Answer:

\boxed{\red{\sf\:\dfrac{\sin\:\theta\:+\:\cos\:\theta}{\sec\:\theta\:+\:\csc\:\theta}\:=\:\dfrac{1}{2}}}

Step-by-step-explanation:

We have given that, \tan\:\theta\:=\:\sf\:1

From trigonometry table, we know that,

\tan\:\sf\:45^{\circ}\:=\:1\\\\\\\therefore\sf\:\theta\:=\:45^{\circ}

We have to find the value of

\sf\:\dfrac{\sin\:\theta\:+\:\cos\:\theta}{\sec\:\theta\:+\:\cosec\:\theta}\\\\\\\sf\:Now\:,\\\\\\\longrightarrow\sf\:\sin\:\theta\:=\:\sin\:45^{\circ}\:=\:\dfrac{1}{\sqrt{2}}\\\\\\\longrightarrow\sf\:\cos\:\theta\:=\:\cos\:45^{\circ}\:=\:\dfrac{1}{\sqrt{2}}\\\\\\\longrightarrow\sf\:\sec\:\theta\:=\:\sec\:45^{\circ}\:=\:\sqrt{2}\\\\\\\longrightarrow\sf\:\csc\:\theta\:=\:\csc\:45^{\circ}\:=\:\sqrt{2}

Now,

\sf\:\dfrac{\sin\:\theta\:+\:\cos\:\theta}{\sec\:\theta\:+\:\csc\:\theta}\\\\\\\sf\:=\:\dfrac{\sin\:45^{\circ}\:+\:\cos\:45^{\circ}}{\sec\:45^{\circ}\:+\:\csc\:45^{\circ}}\\\\\\\displaystyle\sf\:=\:\dfrac{\dfrac{1}{\sqrt{2}}\:+\:\dfrac{1}{\sqrt{2}}}{\sqrt{2}\:+\:\sqrt{2}}\\\\\\\displaystyle\sf\:=\:\dfrac{\dfrac{1\:+\:1}{\sqrt{2}}}{2\:\sqrt{2}}\\\\\\\displaystyle\sf\:=\:\dfrac{\dfrac{2}{\sqrt{2}}}{2\:\sqrt{2}}

\displaystyle\sf\:=\:\dfrac{2}{\sqrt{2}}\:\div\:2\:\sqrt{2}\\\\\\\sf\:=\:\dfrac{\cancel2}{\sqrt{2}}\:\times\:\dfrac{1}{\cancel{2}\:\sqrt{2}}\\\\\\\sf\:=\:\dfrac{1}{\sqrt{2}\:\times\:\sqrt{2}}\\\\\\\sf\:=\:\dfrac{1}{(\:\sqrt{2}\:)^2}\\\\\\\sf\:=\:\dfrac{1}{2}\\\\\\\therefore\boxed{\red{\sf\:\dfrac{\sin\:\theta\:+\:\cos\:\theta}{\sec\:\theta\:+\:\csc\:\theta}\:=\:\dfrac{1}{2}}}

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Additional Information:

\begin{array}{|c|c|c|c|c|c|}\cline{1-6}\multicolumn{6}{|c|}{\sf\:Trigonometric\:Table}\\\cline{1-6}\multicolumn{1}{|c|}{\sf\:Trigonometric\:ratio} & \multicolumn{5}{|c|}{\sf\:Angle\:(\:\theta\:)}\\\cline{1-6}& \sf\:0^{\circ} & \sf\:30^{\circ} & \sf\:45^{\circ} & \sf\:60^{\circ} & \sf\:90^{\circ}\\\cline{1-6}\sin\:\theta	& \sf\:0 & \sf\dfrac{1}{2} & \sf\dfrac{1}{\sqrt{2}} & \sf\dfrac{\sqrt{3}}{2} & 1\\\cline{1-6}\cos\:\theta & \sf\:1 & \sf\dfrac{\sqrt{3}}{2} & \sf\dfrac{1}{\sqrt{2}} & \sf\dfrac{1}{2} & 0\\\cline{1-6}\tan\:\theta & \sf0 & \sf\dfrac{1}{\sqrt{3}} & \sf1 & \sf\sqrt{3} & \sf\:Not\:de fined\\\cline{1-6}\end{array} \begin{array}{|c|c|c|c|c|c|}\cline{1-6}\multicolumn{6}{|c|}{\sf\:Trigonometric\:Table}\\\cline{1-6}\multicolumn{1}{|c|}{\sf\:Trigonometric\:ratio} & \multicolumn{5}{|c|}{\sf\:Angle\:(\:\theta\:)}\\\cline{1-6}& \sf\:0^{\circ} & \sf\:30^{\circ} & \sf\:45^{\circ} & \sf\:60^{\circ} & \sf\:90^{\circ}\\\cline{1-6}\csc\:\theta\:=\:\sf\:\dfrac{1}{\sin\:\theta} & \sf\:Not\:de fined & \sf\:2 & \sf\:\sqrt{2} & \sf\:\dfrac{2}{\sqrt{3}} & \sf\:1\\\cline{1-6}\sec\:\theta\:=\:\dfrac{1}{\cos\:\theta} & \sf\:1 & \sf \dfrac{2}{\sqrt{3}} & \sf \sqrt{2} & \sf 2 & \sf Not\ de fined\\\cline{1-6}\cot\:\theta\:=\:\dfrac{1}{\tan\:\theta} & \sf Not\ de fined & \sf \sqrt{3} & \sf 1 & \sf \dfrac{1} {\sqrt{3}} & \sf 0\\\cline{1-6}\end{array}

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