I’ve been knocking out the trig problems in this section with minimal difficulty so far, but I’ve run straight into a brick wall on this “Algebraic” part. I’m asked to find sin(x)=0 between [0,2π). If I graphed the unit circle this would be a trivial exercise to show sin(θ)=0 when θ=0 or π.

Where I have trouble is- I’m very explicitly being told here that the solution is ALGEBRAIC, and I’m struggling to figure out a way to rearrange sin(x)=0 to come up with the known answer. Further, unit circles are not in this chapter, they wouldn’t likely ask me to exercise a skill taught in another chapter. What am I missing?

It’s not just 31, either. Looking ahead at eg 37, I can easily show sin(-x) = -sin(x) on a unit circle. I could maybe fuck around with inverse trig ratios but those are in section 3- this is only section 1.

Help me out here, drop a hint, share a link: how do I solve sin(x)=0 on [0,2π), but algebraically? I suspect it’s something glaringly obvious and/or very very simple I’ve overlooked.

  • myslsl@lemmy.world
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    8 months ago

    Okay, I see. I’m fucking blind and did not see the words “algebraic” literally at the top of the screenshot.

    For what it is worth, they could just be referring to how they are representing the problems they are asking rather than the form of the intended solutions with that.

    • DarkNightoftheSoul@mander.xyzOP
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      8 months ago

      You think… because they wrote the instructions in the form let f(x) = sin(x)… that that… that’s what they mean… by algebraic?

      god help me I fear you may be right…