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anonymous
 one year ago
Find all solutions in the interval [0, 2π).
sin2 x + sin x = 0
anonymous
 one year ago
Find all solutions in the interval [0, 2π). sin2 x + sin x = 0

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i give medals! please help!

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0you can factor the common term of sin x sin² x + sin x = 0 (sin x)(sin x + 1) = 0 Now set both factors equal to 0 and solve these two equations sin x = 0 sin x + 1 = 0

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i only have a few more minutes to answer this please help and explain!

Australopithecus
 one year ago
Best ResponseYou've already chosen the best response.2So you have, \[\sin^2(x) + \sin(x) = 0\] By the definition of a exponent \[x^2 = x*x\] etc so, \[\sin^2(x) + \sin(x) = 0\] can be written as: \[\sin(x)\sin(x) + \sin(x) = 0\] Now you can factor out sin(x): \[\sin(x)(\sin(x) + 1) = 0\] Now look at both terms sin(x) and (1 + sin(x)) When one of them equals 0 you have a solution

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0sin² x and sin x have a common term of sin x so it can be factored out giving the equation as (sin x)(sin x + 1) = 0 If two thing multiply to be 0, one or both of them is 0. so we can write thes the two equations sin x = 0 and sin x + 1 = 0 To solve sin x = 0, look on the unit circle and pick out all the angle where sine is 0. To solve sin x + 1 = 0, subtract the 1 from both sides sin x = 1 now pick out the angles that have a sine of 1.

Australopithecus
 one year ago
Best ResponseYou've already chosen the best response.2so for (1 + sin(x)) = 0 sin(x) must equal  1 what value of x makes sin(x) = 1? For the second term sin(x) = 0 what value of x makes sin(x) equal 0 Look at the graph of sin(x) http://www.wolframalpha.com/input/?i=graph+of+sin%28x%29+between+0+and+2pi

Australopithecus
 one year ago
Best ResponseYou've already chosen the best response.2Remember that you are only looking for solutions for the interval [0,2pi)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0is there answer x= 0,pi,4pi/3,5pi/3?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.00 and pi are solutions to sin x = 0. the other two aren't solutions to either equation. Where is sine equal to 1 between 0 and 2pi?

Australopithecus
 one year ago
Best ResponseYou've already chosen the best response.2when x = 0 sin(0) = 0 so x =0 is a solution sin(4pi/3) does not equal 0 or 1 so it is not a solution sin(5pi/3) does not equal 0 or 1 so it is not a solution sin(pi) = 0 so it is a solution

Australopithecus
 one year ago
Best ResponseYou've already chosen the best response.2Look at the interval 0 to 2pi It is just the top section of the unit circle

Australopithecus
 one year ago
Best ResponseYou've already chosen the best response.2If you found my help useful please rate me using the qualified help located at the top

Australopithecus
 one year ago
Best ResponseYou've already chosen the best response.2So I can get paid :)

Australopithecus
 one year ago
Best ResponseYou've already chosen the best response.2Not that I wouldnt have helped you for free :)

Australopithecus
 one year ago
Best ResponseYou've already chosen the best response.2Click this button :)

Australopithecus
 one year ago
Best ResponseYou've already chosen the best response.2Ha brain is in stupid mode right now Click rate qualified helper so the button next to it
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