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ASAPT
 one year ago
Find a possible solution to the equation sin (3x+13)=cos(4x)
ASAPT
 one year ago
Find a possible solution to the equation sin (3x+13)=cos(4x)

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ASAPT
 one year ago
Best ResponseYou've already chosen the best response.0its part of my geometry course @LegendarySadist trig is one of the sections lol

ASAPT
 one year ago
Best ResponseYou've already chosen the best response.0@misssunshinexxoxo @ybarrap

ASAPT
 one year ago
Best ResponseYou've already chosen the best response.0nah at my schools it goes algebra 1 geometry algebra 3 and pre calc or discrete math im in geometry summer school

freckles
 one year ago
Best ResponseYou've already chosen the best response.3use a cofunction identity

freckles
 one year ago
Best ResponseYou've already chosen the best response.3for example, recall one of the cofunction identities is: \[\cos(u)=\sin(\frac{\pi}{2}u)\]

ASAPT
 one year ago
Best ResponseYou've already chosen the best response.0wow that really confused me

freckles
 one year ago
Best ResponseYou've already chosen the best response.3why does it confuse you?

ASAPT
 one year ago
Best ResponseYou've already chosen the best response.0because this stuff is like another language to me

freckles
 one year ago
Best ResponseYou've already chosen the best response.3but why does the identity confuse you?

freckles
 one year ago
Best ResponseYou've already chosen the best response.3is it because you never seen it?

ASAPT
 one year ago
Best ResponseYou've already chosen the best response.0kinda this is my first time learning this

freckles
 one year ago
Best ResponseYou've already chosen the best response.3dw:1436410191044:dw

freckles
 one year ago
Best ResponseYou've already chosen the best response.3could you find cos(theta) and sin(90theta) using this right triangle ?

freckles
 one year ago
Best ResponseYou've already chosen the best response.3dw:1436410266489:dw

freckles
 one year ago
Best ResponseYou've already chosen the best response.3\[\sin(90\theta)=\frac{v}{c} \text{ and } \cos(\theta)=\frac{v}{c} \\ \text{ that means } \sin(90\theta)=\cos(\theta) \\ \] of course this is all true if we are working in degress

freckles
 one year ago
Best ResponseYou've already chosen the best response.3since I used 90 deg there

freckles
 one year ago
Best ResponseYou've already chosen the best response.3but we can do the same thing for radians and say \[\sin(\frac{\pi}{2}\theta)=\cos(\theta)\]

freckles
 one year ago
Best ResponseYou've already chosen the best response.3\[\sin(3x+13)=\cos(4x) \\ \text{ by cofunction identity you have that you can find a solution from } \\ \text{ setting the insides of this thingy equal } \\ \sin(3x+13)=\sin(\frac{\pi}{2}4x)\]

ASAPT
 one year ago
Best ResponseYou've already chosen the best response.0so what would that make the answer be?

freckles
 one year ago
Best ResponseYou've already chosen the best response.3set the insides equal

freckles
 one year ago
Best ResponseYou've already chosen the best response.3\[3x+13=\frac{\pi}{2}4x \]

ASAPT
 one year ago
Best ResponseYou've already chosen the best response.0I still don't get my answer

freckles
 one year ago
Best ResponseYou've already chosen the best response.3to solve a linear equation first you do: you put all your x terms on one side and your nonx terms on the opposing side by adding and subtracting stuff on both sides

freckles
 one year ago
Best ResponseYou've already chosen the best response.3your answer should have pi in it somewhere so 11 isn't the answer

freckles
 one year ago
Best ResponseYou've already chosen the best response.3or a answer in this case

freckles
 one year ago
Best ResponseYou've already chosen the best response.3In general to solve the linear equations of the form ax+b=cx+d you do: \[ax+b=cx+d \\ \text{ subtract} cx \text{ on both sides } axcx+b=cxcx+d \\ \text{ now } axcx=(ac)x \text{ and } cxcx=0 \\ \text{ so we have } (ac)x+b=0+d \\ \text{ now subtract } b \text{ on both sides } (ac)x+bb=db \\ (ac)x+0=db \\ (ac)x=db \\ \text{ now final step is to divide }(ac) \text{ on both sides } \\ \text{ so we have } x=\frac{db}{ac}\]

ASAPT
 one year ago
Best ResponseYou've already chosen the best response.0the options are 11 13 13 and 0

freckles
 one year ago
Best ResponseYou've already chosen the best response.3oh then you didn't have to find a possible solution using any identities just plug in those numbers to see which gives you the same thing on both sides

ASAPT
 one year ago
Best ResponseYou've already chosen the best response.0so what would the answer come out to be

freckles
 one year ago
Best ResponseYou've already chosen the best response.3have you tried pluggin in the choices as I suggested above?

ASAPT
 one year ago
Best ResponseYou've already chosen the best response.0i only have 1 minute until i have to submit it

freckles
 one year ago
Best ResponseYou've already chosen the best response.3I think they mean all of that to be in degrees so put your calculator on degrees and see which of the following is true: \[\sin(3(0^o)+13^o)=\cos(4(0^o) ) \\ \sin(3(11^o)+13^o)=\cos(4(11^o)) \\ \sin(3(13^o)+13^o)=\cos(4(13^o)) \\ \sin(3(13^o)+13^o)=\cos(4(13^o))\]

freckles
 one year ago
Best ResponseYou've already chosen the best response.3you can definitely rule out the first since we know sin(13 deg) isn't cos(0 deg) then check the second equation with 11 degs and so on... until you have the same thing on both sides

freckles
 one year ago
Best ResponseYou've already chosen the best response.3what is sin(3*11 deg+13 deg)=?

freckles
 one year ago
Best ResponseYou've already chosen the best response.3give you a hint 3*11+13=33+13=46 and guess what 9046 is?

freckles
 one year ago
Best ResponseYou've already chosen the best response.3recall the above you can do this part without calculator come on you know sin(x)=cos(90x) so sin(46)=cos( ? )

freckles
 one year ago
Best ResponseYou've already chosen the best response.3also it would be helpful in the future if you say if we are working in deg or radians because I thought it was radians until I seen your choices
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