Hello !
cos (a+b) = cos a cos b - sin a sin b
sin (a+b) = sin a cos b + sin b cos a
cos (a+b+c) = cos (a+(b+c))
cos (a+b+c) = cos a cos (b+c) - sin a sin (b+c)
cos (a+b+c) = cos a (cos b cos c - sin b sin c) - sin a (sin b cos c + sin c cos b)
cos (a+b+c)=cos a cos b cos c - cos a sin b sin c - sin a sin b cos c - sin a cos b sin c
Answer:
4x-7=x+2
3x=9
x=3
3-50=-47
Step-by-step explanation:
The answer is D. 27
54 divided by 2 is 27
Answer:
b) 1000x + 115
Step-by-step explanation:
C = 20y + 15
= 20(50x + 5) + 15
= 1000x + 100 + 15
= 1000x + 115
