How do you verify the identity #cos(pi/2+x)=-sinx#?

1 Answer
Write your answer here...
Start with a one sentence answer
Then teach the underlying concepts
Don't copy without citing sources
preview
?

Answer

Write a one sentence answer...

Answer:

Explanation

Explain in detail...

Explanation:

I want someone to double check my answer

Describe your changes (optional) 200

32
sjc Share
Nov 29, 2016

Answer:

use #" "cos(A+B)=cosAcosB-sinAsinB#

Explanation:

#cos((pi/2)+x)=cos(pi/2)cosx-sin(pi/2)sinx#

#cos(pi/2)=0" "sin(pi/2)=1#

#cos((pi/2)+x)=cancel(cos(pi/2)cosx)^0-cancel(sin(pi/2))^1sinx#

#=-sinx#

Was this helpful? Let the contributor know!
1500