Hello :
<span> sin 2x = sin x and 0 ≤ x ≤ 2π.
all solutions :
2x= x +2k</span>π or x= π -x +2kπ ..... k in : Z
x = 2kπ or : x = π/2 + kπ
but :
<span>0 ≤ x ≤ 2π
</span><span>all values of x such that sin 2x = sin x and 0 ≤ x ≤ 2π are :
</span>k = 0 : x=0 , x= π/2
k=1 : x=2 π , x=3π/2
Let b and s be the velocity of the boat and stream respectively....
3(b-s)=27
b-s=9
b=9+s we will use this in the second equation....
2(b+s)=30
b+s=15, now use b found above in this to get:
9+s+s=15
2s+9=15
2s=6
s=3, and since from earlier b-s=9, b=9+s so
b=12
So the speed of the boat is 12mph and the stream is 3 mph
Step-by-step explanation:
To find the volume of a rectangular prism V=whl so w=3 x 5 x 12. Multiply all those numbers together to get 180 inches cubed.