proving a trig identitie

[nevellsb]

Hey i need help proving this

cos(x-(pi/4))-cos(x+(pi/4))= (√2)(sinx)

I must use and be able to label the identity applied to the function, as, algebra, reciprocal, quotient, pythagorean,evaluation,
sum or distance

thank you

 

[Deleted member 4993]

Hey i need help proving this

cos(x-(pi/4))-cos(x+(pi/4))= (√2)(sinx)

I must use and be able to label the identity applied to the function, as, algebra, reciprocal, quotient, pythagorean,evaluation,
sum or distance

thank you

What would you call the identity:

Cos(A+B) = Cos(A)*Cos(B) - Sin(A)*Sin(B)