ImDecentAtMath

10 Questions
89 Answers

+1

448

10

+189

My friend had an interesting question I found hard. Help appreciated!

Consider the following points (a,4/5) and (b,4/5) on the graph of y=cos(x) and (a,c) and (b,d) on the graph of y=cos(x+pi/6).
Furthermore, -pi/2

●●●●●●●●●●

ImDecentAtMath Jan 19, 2022

0

347

1

+189

Try this out

How many even, three-digit positive integers have the property that two of the digits are equal, but not all three are equal?

ImDecentAtMath Jan 19, 2022

0

336

2

+189

Try this problem, should be pretty easy if you understand how to do it:

Try this problem, should be pretty easy if you understand how to do it:
c+b-t=170
t+b-c=130
What is b? read more ..

ImDecentAtMath Jan 19, 2022

0

323

0

+189

Melody, could you help with the error here

So Melody, in this link, https://web2.0calc.com/questions/interesting-problem-my-friend-had-for-me
it was not letting me type in the actual question after I typed -pi/2 and even when I tried editing it wasn't changing. Please help and thank read more ..

ImDecentAtMath Jan 19, 2022

+1

389

5

+189

Off-topic

I got on the leaderboard on this very day when I made my account!

off-topic

●●●●●

ImDecentAtMath Jan 18, 2022

0

372

4

+189

Interesting problem my friend had for me

Consider the following points (a,4/5) and (b,4/5) on the graph of and (a,c) and (b,d) on the graph of .
Furthermore, -pi/2

ImDecentAtMath Jan 18, 2022

0

363

1

+189

Melody pls help

So I saw Melody's hint from this link: https://web2.0calc.com/questions/pls-help-if-possible
but I didn't understand how to use it. If you are able to, please help.
Also, I had a question at this link: https://web2.0calc.com/questions/idk-how-to-do-this_6#r4 read more ..

ImDecentAtMath Jan 18, 2022

0

423

14

+189

Pls help if possible

Calculate sin([arccos(-1/9)]/2) and put the answer as a fraction.

●●●●●●●●●●●●●●

ImDecentAtMath Jan 18, 2022

0

388

10

+189

Idk how to do this

Calculate
Answer in radians.

●●●●●●●●●●

ImDecentAtMath Jan 18, 2022

0

347

1

+189

Precalculus Problem which I'm confused on

There are integers a, b, c, and d such that . Answer with (a+b), (c+d) in that order.

ImDecentAtMath Jan 17, 2022

+189

0

I could use a unit circle and then use the Pythagorean Theorem to say sin(theta)^2+(1/9)^2=1^2 or sin(theta)^2=80/81. This leads to sin(theta)=(sqrt80)/9.

Am I correct because I feel like I did something wrong?

And if I got sin(theta) right, how can I evaluate sin(theta/2)?

ImDecentAtMathJan 18, 2022

+189

-1

Could you do it without the LaTeX symbols since it's hard to read.

ImDecentAtMathJan 18, 2022

+189

-1

That question doesn't make sense logically. Maybe your question was BD=CD? Because D is on BC and so BC can never be BD.

ImDecentAtMathJan 18, 2022

+189

-1

I figured it out in the end. It is 13pi/96.

ImDecentAtMathJan 18, 2022

+189

-1

So basically, it's the arccos of -1/9, then that divided by 2, and then the sin of that.

ImDecentAtMathJan 18, 2022

+189

-1

Sorry, I got confused. I will explain why. The context of this problem is cos(theta)=-1/9 and cos(theta/2)<0. And I am trying to find the sin(theta/2). When I was finding cos(theta/2) I did arccos(-1/9) then divided that by two, and did the cosine of that.

ImDecentAtMathJan 18, 2022

+189

0

Np, I have been trying for a few hours, and still don't know so I understand if it's hard. :)

ImDecentAtMathJan 18, 2022

+189

0

cos(theta) would be -2/3

ImDecentAtMathJan 18, 2022

+189

-1

I was trying to find a fractional value, and thought of using the half-angle formulas, but didn't know how to apply them here.

ImDecentAtMathJan 18, 2022

+189

-1

It would be 4. I hope I'm not misunderstanding your question.

ImDecentAtMathJan 18, 2022