Jonathan T.

asked • 12/03/16

Need to simplify

(CosA-cosB)2 + (sinA-sinB)2
 
Can someone help me solve this? and what steps do we take ?

1 Expert Answer

By:

Mark M. answered • 12/03/16

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(cosA - cosB)2 + (sinA - sinB)2
 
= cos2A - 2cosAcosB + cos2B + sin2A - 2sinAsinB + sin2B
 
= (cos2A + sin2A) + (cos2B + sin2B) -2(cosAcosB + sinAsinB)
 
= 1 + 1 -2cos(A-B)
 
= 2 - 2cos(A-B)
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Jonathan T.

THANK YOU! now that i see it like this, it looks alot easier then i thought it would be. 
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12/04/16

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