+0  
 
0
2655
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avatar+55 

What is the value of x?

sin(x+34)°=cos(2x+20)°

Enter your answer in the box.

 

What is the value of x?

sin32°=cosx

Enter your answer in the box.

 

thank you so much!

 Mar 28, 2018
edited by flanspawn  Mar 28, 2018
 #1
avatar+33661 
+3

cos(A - 90°) = cos(A)cos(90°) + sin(A)sin(90°)  or  cos(A - 90°) = cos(A)*0 + sin(A)*1 or cos(A - 90°) = sin(A)

 

If A = x + 34, then sin(x + 34) can be written as cos(x + 34 - 90) or cos(x - 56)

 

So if sin(x+34) = cos(2x + 20) we could also write  cos(x - 56) = cos(2x + 20) which means that x - 56 = 2x + 20 

 

rearranging, we have: x = -76°  

 

Check:

 

sin(-76+34) = -0.6691

cos(2*(-76)+20) = -0.6691

 

 

If you want a value of x between 0 and 360, simply add 360 to x (i.e 360 - 76 = 284).

 Mar 28, 2018
edited by Alan  Mar 28, 2018
 #2
avatar
+1

What is the value of x?

sin32°=cosx

Enter your answer in the box

 

sin(32) = cos(x)

x = 90 - 32

x = 58, so that:

sin(32) = cos(58)

 Mar 28, 2018

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