anonymous one year ago Find all solutions to the equation. sin2x + sin x = 0 @johnweldon1993

1. Nnesha

take out common factor let sin x=y so y^2 +y what's the common factor ?

2. johnweldon1993

This is $$\large sin^2(x) + sin(x) = 0$$ right? or $$\large sin(2x) + sin(x) = 0$$ ?

3. anonymous

no first one lol

4. johnweldon1993

Then perfect go ahead with the process @Nnesha was showing :) Look at it as sin(x) = y so sin^2(x) = y^2 $\large y^2 + y = 0$ What can you factor out?

5. xapproachesinfinity

still troubled by this or solved it

6. anonymous

troubled @xapproachesinfinity

7. xapproachesinfinity

so you have no idea how to factor y^2+y=0? what is common btw y^2 and y?

8. xapproachesinfinity

let's us go to the basics how can you do this a(b+c)=? using distributive law?

9. xapproachesinfinity

i want you to interact with me otherwise i will just take my leave haha

10. anonymous

sorry i was doing somethin away from the laptop.. but i have NO IDEA how to do this ABSOLUTELY NONE!

11. anonymous

@Nnesha

12. Nnesha

yes?

13. xapproachesinfinity

ok back let's pick it up where i left it know of distributive law?

14. anonymous

nope :( im so sorry im making this hell for u wish i did :/

15. xapproachesinfinity

realize that is the basic math? from lower grades

16. xapproachesinfinity

so distributive law tells us that a(b+c)=ab+ac the left hand side is the same are the right hand side any doubt that it true?

17. xapproachesinfinity

same as*

18. xapproachesinfinity

well?

19. anonymous

wat?

20. xapproachesinfinity

i said do you agree that a(b+c)=ab+ac or against this arithmetic law? the problem here is we need to establish some sense first before we tackle that problem of your that deals with trig

21. anonymous

yes

22. xapproachesinfinity

so you have no problem to tell what this is gonna be bd+be=? using the same law?

23. xapproachesinfinity

oh well! so it is gonna be bd+be=b(d+e) yes?

24. anonymous

yes

25. xapproachesinfinity

now tell me what did i just do?

26. xapproachesinfinity

describe me what i did?

27. anonymous

u factored y^2 and y

28. xapproachesinfinity

no just stay on what i did that would come later! what i'm trying to do here to show you how we can accomplish the factorization for y^2+y

29. anonymous

oh ok got it

30. xapproachesinfinity

i want you to fully understand this! so you will have further problem with such exercice!

31. xapproachesinfinity

so here really what i did is using the that very distributive law of arithmetic to get from bd+be to b(d+e)

32. anonymous

alright got it

33. xapproachesinfinity

ok let me test one more time xy+2x=?

34. xapproachesinfinity

again distributive law!

35. anonymous

nvm

36. xapproachesinfinity

this is all for the sake of you being better at this, if that's the case then it is really fine with me we can gave you the answer, but what is the point of doing it any way

37. xapproachesinfinity

give*

38. Nnesha

one more try y^2 + y let y = chocolates exponent represents number of chocolates |dw:1433891939844:dw| how many chocolates they both people have n common ?

39. anonymous

i just don't get it and it makes me feel really dumb :/

40. xapproachesinfinity

i can tell oh this and that an such then this is the answer next time you have test you stuck! who is there to give you the answer no one no you are not dumb. you are resisting this is that is all

41. anonymous

ok explain to me step by step n slo like nnesha and i'll try my best to understand

42. xapproachesinfinity

ok i guess nnesha might have a better approach than me hehe

43. anonymous

@Nnesha

44. Nnesha

nah you explained MUCH MUCH better than me

45. Nnesha

read my 2nd last comment y^2 + y what is common in these both terms ?

46. xapproachesinfinity

well the outcome is that she didn't understand me so perhaps some fancy art gets the idea across

47. xapproachesinfinity

you never know! people learn differently haha

48. xapproachesinfinity

for me i'm very systematic!

49. Nnesha

that's great!!!!

50. xapproachesinfinity

nah artistic is also needed for much better result in maths! math is more fun if those are combined

51. Nnesha

alright barbiegirl so http://prntscr.com/7f5mgb?

52. Nnesha

that's right but *practice* is MORE important -taking notes -solve one question more than 3 times it will help to memorize stuffff

53. xapproachesinfinity

yeah! practice is about everything! whether it be math or anything

54. xapproachesinfinity

well have to leave now sorry iambarbie :)

55. Nnesha

i'm still waiting for ur reply i have 10 mints

56. anonymous

wat do u want me to do? u just drew a pic explaining it to me..

57. Nnesha

i asked a question how many chocolates they both people have n common ?

58. anonymous

both have 3

59. Nnesha

how ?? remember exponent represent number of chocolates |dw:1433893136376:dw|

60. anonymous

once has 2 and the other has 1

61. Nnesha

so common number of chocolate would be one right or you can apply exponent rule $\huge\rm x^m \times x^n = x^{m +n}$ so that's how y times y = y^2$\huge\rm (y \times y \color{red}{+} y)$ so what's common in thes both terms ?

62. anonymous

will u be on an hour later or something like that?

63. Nnesha

alright

64. anonymous