Welcome to Westonci.ca, the ultimate question and answer platform. Get expert answers to your questions quickly and accurately. Get quick and reliable answers to your questions from a dedicated community of professionals on our platform. Experience the ease of finding precise answers to your questions from a knowledgeable community of experts.
Sagot :
Answer:
cos 4x
Step-by-step explanation:
[tex]( \cos 3x)( \cos x) − ( \sin 3x)( \sin x) \\ \\ = \cos \: (3x + x) \\ \\ = \cos \: 4x[/tex]
The result for the expression (cos 3x)(cos x) − (sin 3x)(sin x) is cos 4x.
Trigonometric Identities
What is trigonometric identities ?
Equations involving trigonometric functions that hold true for all possible values of the variables are known as trigonometric identities.
The addition/sum formula in trigonometry:
In terms of functions of A and B, angle addition formulae express trigonometric functions of sums of angles A[tex]\frac{+}{_}[/tex]B.
Sum formula or cos:
cos (A+B) = cosA.cosB + sinA.sinB
Application of sum formula of cos:
The give equation is as follows,
(cos 3x)(cos x) − (sin 3x)(sin x)
Applying the sum formula,
= (cos 3x)(cos x) − (sin 3x)(sin x)
= cos(3x + x)
= cos 4x
Therefore, the result of the given equation is cos 4x.
To know more about trigonometric ratios and their examples, here
https://brainly.com/question/24349828
#SPJ2
Your visit means a lot to us. Don't hesitate to return for more reliable answers to any questions you may have. Thank you for visiting. Our goal is to provide the most accurate answers for all your informational needs. Come back soon. Stay curious and keep coming back to Westonci.ca for answers to all your burning questions.