Rule 1: The product<span> of a positive </span>integer<span> and a negative </span>integer<span> is a negative </span>integer<span>. Rule 2: The </span>product of two<span> negative </span>integers<span> or </span>two<span> positive </span>integers<span> is a positive </span><span>integer</span>
Answer:
the angle is changing at a rate of 0.0375 rad/s when the time is t=8 seconds
Step-by-step explanation:
since the line D that starts from the spectator and follows the plane has the following equation
D² = x² + H² , where H= altitude of the plane , x= horizontal distance
then for x=v*t , where v=speed of the plane and t=time since the plane has passed overhead , we have for the elevation angle
tan θ = x/y = v*t /H
θ = tan⁻¹ ( v*t /H)
the rate of change in the angle of the spectator's sight θ with the time is
dθ/dt = 1/1+(v*t /H)² * (v/H) = (v/H)/[1+ (v/H)²*t²]
for t=8 seconds
dθ/dt = (875 ft/s/21000 ft)/[1+ (875 ft/s/21000 ft)²*(8 s)²] = 0.0375 rad/s
therefore the angle is changing at a rate of 0.0375 rad/s when the time is t=8 seconds
Answer:
The correct option is C). When it was purchased, the coin was worth $6
Step-by-step explanation:
Given function is f(t)=
Where t is number of years and f(t) is function showing the value of a rare coin.
A figure of f(t) shows that the graph has time t on the x-axis and f(t) on the y-axis.
Also y-intercept at (0,6)
hence, when time t was zero, the value of a rare coin is 6$
f(t)=
f(0)=
<em>f(0)=6</em>
Thus,
The correct option is C). When it was purchased, the coin was worth $6
Answer:
1 : 51 2 : 39 3 : 90
Step-by-step explanation:
1 : 180(internal angle of triangle) - 90 - 39 =51
2. alternate angles
3. internal angles of rectangle are always 90
Multiples of 5: <span>5, 10, 15, 20, 25
</span>Multiples of 1<span>: 1, 2, 3, 4, 5
</span>Multiples of 4<span>: 4, 8, 12, 16, 20</span>