Darryl:
Answer:
A = $1,905.00
(I = A - P = $405.00)
Equation:
A = P(1 + rt)
Lori:
Answer:
A = $1,932.00
(I = A - P = $532.00)
Equation:
A = P(1 + rt)
Thus $532-$405= $127 more in Lori's account
As usual, draw a diagram. You can easily see that if you are x away from the wall,
<span>the angle of elevation of the bottom of the screen (A) is </span>
<span>cotA = x/3 </span>
<span>A = arccot(x/3) </span>
<span>angle B to the top is </span>
<span>cotB = x/10 </span>
<span>B = arccot(x/10) </span>
<span>So, since θ = B-A </span>
<span>dθ/dt = dB/dt - dA/dt </span>
<span>= -3/(x^2+9) + 10/(x^2+100) </span>
<span>= 7(x^2-30)/((x^2+9)(x^2+100)) </span>
<span>so, at x=30 </span>
<span>dθ/dt = 203/30300</span>
Sang grew more. and by 17/40 ( I could be wrong)