Cos(A-B) = cosAcosB + sinAsinB
<span>
cos(</span>π/2 - θ) = cos(π/2)cosθ + sin(π/2)sinθ
π/2 = 90°
cos(π/2) = cos90° = 0. sin(π/2) = sin90° = 1
cos(π/2 - θ) = cos(π/2)cosθ + sin(π/2)sin<span>θ
</span>
= 0*cosθ + 1*sin<span>θ = </span>sin<span>θ
Therefore </span>cos(π/2 - θ) = sin<span>θ
QED </span>
3 3/4 + 1 1/4 + 2 2/4
3/4 + 1/4 + 2/4 = 1 1/2
3 + 1 + 2 + 1 1/2 = 7 1/2 cups total
Answer:
w =< 70
(width is less or equal to 70 inches)
Step-by-step explanation:
Let l = length, w = width, h = height
Restrictions given in this question:
'sum of perimeter of the base and the height cannot exceed 130 inches'
perimeter of the base is 2 width and 2 length of the box
perimeter = 2w + 2l
Therefore, inequality involves here is
2w + 2l + h =< 130
(Note that =< here means less or equal)
Then a new condition given with
height, h = 60 in
and length is 2.5 times the width
l = 2.5w
Substitute this new condition into the equation will give us the following:
2w + 2(2.5w) + 60 =< 130
2w + 5w + 60 =< 130
7w + 60 =< 130
7w =< 130-60
7w =< 70
w =< 10
I HOPE IT WILL HELP YOU. I DID HOW I KNOW .