Assuming the question marks are minus signs
to find max, take derivitive and test 0's and endpoints
take derivitive
f'(x)=18x²-18x-108
it equal 0 at x=-2 and 3
if we make a sign chart to find the change of signs
the sign changes from (+) to (-) at x=-2 and from (-) to (+) at x=3
so a reletive max at x=-2 and a reletive min at x=3
test entpoints
f(-3)=83
f(-2)=134
f(3)=-241
f(4)=-190
the min is at x=3 and max is at x=-2
You can multiply 3 and 6 together then divide the product by 2
(6*3)/2=18/2=9
The distance of the ball from the foot of the tower is : 35.18m
The ball would be moved 57.2m away from the foot of the tower for the Angle of elevation to be halved.
<h3>What is angle of elevation?</h3>
Angle of elevation is the angle formed between the horizontal and the line of view from the vertical.
Analysis:
The height of the tower and the distance of the ball from the foot of the tower form a right angle triangle.
so we use trigonometry.
a) let distance of the ball from foot of tower be x.
so that, tan 52 = 45/x
x = 45/tan52
x = 45/1.279 = 35.18m
b) let the distance of the ball in the new position from the foot of the tower be y.
if the angle of elevation is halved, then new angle is 52/2 = 26°
tan 26 = 45/y
y = 45/tan26 = 45/0.487 = 92.4m
distance moved from old position to new position = 92.4 - 35.18 = 57.2m
In conclusion, the distance of the ball from the foot of the tower and the distance the ball should move to make its elevation 26° are 35.18m and 57.2m respectively.
Learn more about angle of elevation: brainly.com/question/88158
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700 x .03 x 20 = 420
420 + 700
1120 is in the account after 20 years