The the parabola opens upward it has a minimum and if it opens downward then it has a maximum :)
we are given

we can check each options
option-A:
-1,1
we can plug x=-1 and x=1 and check whethet f(x)=0
At x=-1:


At x=1:


so, this is TRUE
option-B:
0,1
we can plug x=0 and x=1 and check whethet f(x)=0
At x=0:


At x=1:


so, this is FALSE
option-C:
-2,-1
we can plug x=-2 and x=-1 and check whethet f(x)=0
At x=-2:


At x=-1:


so, this is FALSE
option-D:
-1,0
we can plug x=-1 and x=0 and check whethet f(x)=0
At x=-1:


At x=0:


so, this is FALSE
They seem to be very descriptive and use lots of examples of nature.
Answer:
B
Step-by-step explanation:
Answer:
cos x = 8/f.
Step-by-step explanation:
We can use the identity :
tan x = sin x / cos x.
Substituting:
e/8 = e/f / cos x
e/8 * cos x = e/f
cos x = e/f * 8/e
cos x = 8e / fe
cos x = 8/f.