find the solution sets for
-secx+tanx=0
-sinxtanx=0
-sin2x+sin3x=0

Question

find the solution sets for 
 ->secx+tanx=0
 ->sinxtanx=0
 ->sin2x+sin3x=0

perl · Answer

are these two separate equations?

czarluc · Answer

yes

czarluc · Answer

would be great if all are answered :)

anonymous · Answer

Could you edit them to show it's 2 because im confused.

czarluc · Answer

actually there are three questions lol

solomonzelman · Answer

$\large\color{black}{ \sec x+\tan x=0}$
$\large\color{black}{ \sec x=-\tan x}$
square both sides,
$\large\color{black}{ \sec^2x=\tan^2x}$
$\large\color{black}{ \tan^2x+1=\tan^2x}$
your opinion?

czarluc · Answer

then it  would be 1=0?

solomonzelman · Answer

yes, and that means that how many solutions are there?

czarluc · Answer

1? sorry I don't know :(

solomonzelman · Answer

No solution, because 1 can't equal zero. (No?)

solomonzelman · Answer

No solution, because 1 can't equal zero. (No?)

czarluc · Answer

the solutions sets I 'm referring to are the angles like in 0<=x<=360

czarluc · Answer

how do you solve this in the forms of trig. equations?

solomonzelman · Answer

$\large\color{black}{ \sin(3x)+\sin(2x)=0}$
$\large\color{black}{ \sin(3x)=-\sin(2x)}$
$\large\color{black}{ \sin(3x)=\sin(-2x)}$
$\large\color{black}{ 3x=-2x}$

solomonzelman · Answer

So x=?

czarluc · Answer

attachment

solomonzelman · Answer

I am not so sure about what the second question is, because it is not equal to anything. You have to right the second question correctly.

solomonzelman · Answer

And yes, x=0 for #3.

solomonzelman · Answer

Oh you did already:)

czarluc · Answer

but when i look it up on the net they say it has like 7 solutions

czarluc · Answer

hahaha thanks

czarluc · Answer

or maybe not seven just not only zero

solomonzelman · Answer

$\large\color{black}{ \tan(x)\sin(x)=0}$

$\large\color{black}{ \tan(x)=0}$     or      $\large\color{black}{ \sin(x)=0}$

solomonzelman · Answer

There can be many solutions. Are you given any intervals?

czarluc · Answer

uhm its 0<=x<=360

solomonzelman · Answer

Ohh, so,  [0,360]

solomonzelman · Answer

When is sin(x)=0 ? when x is what, can you tell me?

solomonzelman · Answer

There are 2 x-solutions.
180º and 360º

solomonzelman · Answer

those questions marks are supposed to be degree signs, nothing more...

czarluc · Answer

sorry for the delay the internet was cut off

solomonzelman · Answer

happens, it's fine:)

czarluc · Answer

would you include 0?

solomonzelman · Answer

yes, since it is a closed interval, the zero is included.

czarluc · Answer

oh so there are three answers?

solomonzelman · Answer

yes

czarluc · Answer

oh ok got it! thanks :)

solomonzelman · Answer

Enjoy...