SOLUTION: if tan theta=10/7, and if cos theta <0 then, sec theta= cos theta= sin theta= tan theta/2= sin 2theta= sin theta/2=

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Question 1103528: if tan theta=10/7, and if cos theta <0 then,
sec theta=
cos theta=
sin theta=
tan theta/2=
sin 2theta=
sin theta/2=
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
if tan theta=10/7, and if cos theta <0 then
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tan + and cos minus --> Q4 --> x is +, y is negative
y = 10
x = -7
=========================
tan = y/x
r = sqrt(x^2+y^2) = sqrt(149)
------------
cos theta= y/r = -10/sqrt(149)
sec theta= 1/cos = -sqrt(149)/10
-----
sin theta= sqrt(1 = cos^2) --- positive in Q4
---
tan theta/2= sin/cos
==============================
sin 2theta= 2sin*cos
------------
sin theta/2= --- Look up "Half Angle formulas" on Wikipedia.