Don'tknowtrig

prnt.sc/jnp0iz PLEASE HELP ME!!!!!

Derive this identity from the sum and difference formulas for cosine: sinasinb=1/2[cos(a-b)cos(a+b)] Start with the right-hand side since it is more complex. Calculations: _____ _____ _____ Reason: _____ _____ _____

Thank you Reiny for the last question! :) If you or anyone else could help me with this other question, I'd really appreciate it! Use the trigonometric subtraction formula for sine to verify the identity: sin(pi/2-x)=cosx Caluculation: ----- ----- ----- R...

Derive this identity from the sum and difference formulas for cosine: sinasinb=1/2[cos(a-b)cos(a+b)] Start with the right-hand side since it is more complex. Calculations: _____ _____ _____ Reasons: _____ _____ _____

OMLLL! Thank you! Ily. :*