So, for the second problem, they've reversed the situation: Now we have the temperature, and we have to think backwards to figure out the number of cricket chirps (in five minutes)!
We ended up with 60 degrees (somehow). Well, let's subtract 37. That gives us 23. What does this number mean? It is the number of times the cricket chirps in 15 seconds. But we want five minutes... I bet you can take it from here... :)
We know that, as per a corollary of intermediate value theorem, if a function f(x) is continuous on a closed interval [a,b], and values of f(a) and f(b) have opposite signs, then the function f(x) is guaranteed to have a zero on the interval (a,b).
So, basically, we need to figure out two values of x, at which the values of the given cubic function have opposite signs.
Let us consider the interval [-2,1].
We have . Upon substituting the values x=-2 and x=1 one by one, we get:
We can see that signs of values of the function at x=-2 and x=1 are opposite, therefore, as per intermediate value theorem, the function is guaranteed to have a zero on the interval [-2,1]
All of my teachers have told me that everyone remembers things best in groups of seven. so I would suggest to pick a continent and start in a corner and spend a couple of days studying seven countries in that area. also quiz your self every once in a while for extra help.
I hope this helps you
Answer:
-5 (3b+4)
Step-by-step explanation:
-15b - 20
-5 (3b+4)
Answer:
36π
Step-by-step explanation: