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trig equation quick question

can someone explain how the first line would become the second, why does the RHS (2θ+40) just cancel out?

Screenshot 2024-04-08 152404.png
(edited 1 year ago)

Reply 1

If you divide 5sin(2x+40) by root3cos(2x+40) you end up with 5/root3 multiplied by sin(2x+40)/cos(2x+40) = 1, since the trig identity means that any sin over cos makes tan, then you have 5/root3 multiplied by tan(2x+40) = 1, then times both sides by root3, then divide by 5 and u end up with tan(2x+40) = root3/5

Reply 2

Original post by shelleydrowning
If you divide 5sin(2x+40) by root3cos(2x+40) you end up with 5/root3 multiplied by sin(2x+40)/cos(2x+40) = 1, since the trig identity means that any sin over cos makes tan, then you have 5/root3 multiplied by tan(2x+40) = 1, then times both sides by root3, then divide by 5 and u end up with tan(2x+40) = root3/5

thank you so much, i left the 1 out when i divided the RHS

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