The answer is 0.03225806451
And -15.5/-0.5 is 31
Let the distance traveled by car X be x km
<span>let the distance traveled by car Y by y km </span>
<span>their paths form a right-angled triangle. </span>
<span>Let the distance between them be D km </span>
<span>D^2 = x^2 + y^2 </span>
<span>2D dD/dt = 2x dx/dt + 2y dy/dt </span>
<span>dD/dt = (x dx/dt + y dy/dt)/D </span>
<span>at the given case: </span>
<span>x = 60, y = 80 , dx/dt = 80, dy/dt = 100 </span>
<span>D^2 = 60^2 + 80^2 = 10000 </span>
<span>D = 100 </span>
<span>dD/dt = (60(80) + 80(100))/100 </span>
<span>= 128 </span>
The parabola opens upward. because 8x^2 is positive
There are 4 terms in the world of *Mathematical proof*
Lemma, Proposition, Corollary and Theorem.
There is no difference between a lemma,
proposition, theorem, or corollary - they are all claims waiting to be proved. However, we use these terms to suggest different levels of importance and difficulty. A lemma is an easily proved claim which is helpful for proving other propositions and theorems, but is usually not particularly interesting in
its own right. A proposition is a statement which is interesting in its own right, while a theorem is a more important statement than a proposition which says something definitive on the subject, and often takes more effort to prove than a proposition or lemma. A corollary is a quick consequence of a proposition or theorem that was proven recently
