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Find, correct to 2 decimal places, the largest solution in the given interval.
3sin(x) + tan(x) = 0 for -180<x<180

so far, I converted tan(x) into sin(x)/cos(x) but then idk what to do next?
Reply 1
Original post by jungkook123
Find, correct to 2 decimal places, the largest solution in the given interval.
3sin(x) + tan(x) = 0 for -180<x<180

so far, I converted tan(x) into sin(x)/cos(x) but then idk what to do next?


Factorize out sin(x)
Reply 2
Original post by mqb2766
Factorize out sin(x)

so would it be sin(x)(3 + 1/cos(x))?
Reply 3
Original post by jungkook123
so would it be sin(x)(3 + 1/cos(x))?

Yes, so treat each term separately and solve for x.
(edited 3 years ago)
Reply 4
Original post by mqb2766
Yes, so great each term separately and solve for x.

what do you mean by great each term
Reply 5
Original post by jungkook123
what do you mean by great each term

You have a product of factors = 0, so one of them must be zero. Just do the usual argument.
Reply 6
Original post by mqb2766
You have a product of factors = 0, so one of them must be zero. Just do the usual argument.

sorry I don't understand what to do
Reply 7
Original post by jungkook123
sorry I don't understand what to do

sin(x)=0
Or
3+1/cos(x)=0
Reply 8
Original post by mqb2766
sin(x)=0
Or
3+1/cos(x)=0

so what do I do now?
Reply 9
Original post by jungkook123
so what do I do now?

What's stopping you solving for x?
Reply 10
Original post by mqb2766
What's stopping you solving for x?

for the 3+1/cos(x) would cos(x)=-1/3?
Original post by jungkook123
for the 3+1/cos(x) would cos(x)=-1/3?

3+1/cos(x)=0
Don't forget the =0.

Yes that is obviously correct.
Reply 12
Original post by mqb2766
3+1/cos(x)=0
Don't forget the =0.

Yes that is obviously correct.

I get it now, thank you for your help!!!

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