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# Can you factorise this? watch

1. I'm trying to do a question

to solve 4sin x = 3 tan x

so, I converted the tan x

into 4sin x = 3sin x /cos x

so I cross multiplied , for it to be 4sin x 3 Cos x = 3 sin x

I subtratced 3 sin x

Hence = 4sin x 3cos x - 3 sin x = 0

can I factorise, if so, any tips or how would you do it?
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3. 4sinx = 3 tanx
4sinx = 3sinx/cosx
4sinx -3sinx/cosx = 0
sinx(4-3/cosx) = 0
so either sinx = 0
or 4 = 3/cosx
4cosx = 3
cosx = 3/4

I think this would be a correct way of doing it, I'm not very awake right now though.

P.S: Be wary of just cancelling out sinx when trying to solve, as you will leave out solutions for sinx = 0
4. (Original post by KatheO11)
I'm trying to do a question

to solve 4sin x = 3 tan x

so, I converted the tan x

into 4sin x = 3sin x /cos x

so I cross multiplied , for it to be 4sin x 3 Cos x = 3 sin x

I subtratced 3 sin x

Hence = 4sin x 3cos x - 3 sin x = 0

can I factorise, if so, any tips or how would you do it?

Then move sine over to the LHS and factor it out.
5. (Original post by Mosa99)
Dividing through by sin(x), in this case, removes some solutions. Instead, everything should be moved to one side, hence making the left-hand side equal to zero. After this the sin(x) should be factorised out and the equation can be solved normally from this point.
6. (Original post by KatheO11)
into 4sin x = 3sin x /cos x

so I cross multiplied , for it to be 4sin x 3 Cos x = 3 sin x
The 3 belongs to the numerator so is alone.

Think of this as and simplify from there
7. (Original post by Mosa99)
..
You should not cancel out the because that would reduce the number of solutions has. Instead, move everything to one side and factorise it out and you'll have and that's one equation to solve for .
8. What a silly mistake I did 😅 Thank you guys for correcting me!!
9. (Original post by Mosa99)
What a silly mistake I did 😅 Thank you guys for correcting me!!
Also it's advisable you don't post solutions in the future
10. (Original post by ManLike007)
Also it's advisable you don't post solutions in the future

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