find the values that satisfy the trigonometric expression.
u have to solve the equation \(\large\tt \begin{align} \color{black}{ \sin \theta + \tan( -\theta) =0\\~\\ \sin \theta - \tan \theta =0\\~\\ \sin \theta - \dfrac{\sin \theta }{\cos \theta }=0\\~\\ \sin \theta(1 - \dfrac{1 }{\cos \theta })=0\\~\\ \sin \theta(1 - \dfrac{1 }{\cos \theta })=0\\~\\ }\end{align}\) see if that makes sense
no not really
which step r u not getting
note that \(tan (-\theta)=-tan \theta\\ and\\ tan \theta =\dfrac{sin \theta}{cos \theta}\)
lol i see now ok
so now u will have two solutions \(\large\tt \begin{align} \color{black}{ \sin \theta(1 - \dfrac{1 }{\cos \theta })=0\\~\\ \sin \theta=0~~or~~\dfrac{1 }{\cos \theta }=0\\~\\ \theta=\sin^{-1}0~~or~~(1-\dfrac{1 }{\cos \theta })=0\\~\\ \theta=\sin^{-1}0~~or~~(\dfrac{1 }{\cos \theta })=1\\~\\ \theta=\sin^{-1}0~~or~~\cos \theta =1\\~\\ \theta=\sin^{-1}0~~or~~\theta =\cos ^{-1}1\\~\\ }\end{align}\) see if thats ok
this one \(\large\tt \begin{align} \color{black}{ \sin \theta(1 - \dfrac{1 }{\cos \theta })=0\\~\\ \sin \theta=0~~or~~(1-\dfrac{1 }{\cos \theta })=0\\~\\ \theta=\sin^{-1}0~~or~~(1-\dfrac{1 }{\cos \theta })=0\\~\\ \theta=\sin^{-1}0~~or~~(\dfrac{1 }{\cos \theta })=1\\~\\ \theta=\sin^{-1}0~~or~~\cos \theta =1\\~\\ \theta=\sin^{-1}0~~or~~\theta =\cos ^{-1}1\\~\\ }\end{align}\)
ok
so can u solve further ?
it should be easy now note that \(0\leq \theta <2\pi\)
tbh i dont really know how to do it any farther this was a sample problem in my book and i am totally lost
ok u need to study unit circle for this
\(\sin 0^{\circ} =0 \\and\\ \sin \pi=0\) similarly \(\cos 0^{\circ} = 1\\and\\ \sin \pi=1\) refer this http://www.mathsisfun.com/geometry/unit-circle.html
sry the last step should be \(cos \pi=1\) not \(sin \pi=1\)
ok im following
so according to the condition unit circle is from \(0\rightarrow 2\pi\) same as ur theta restrictions \(0\leq \theta <2\pi\) so the values which satisfy the answer are \(0\\and \\\pi\)
thanks for explaining it :)
yw
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