Answer:
B = 612.2 ft
Step-by-step explanation:
Solution:-
- The elevation of person, H = 235 ft
- The angle of depression, θ = 21°
- We will sketch a right angle triangle with Height (H), and Base (B) : the boat's distance to the edge of the cliff and the angle (θ) between B and the direct line of sight distance.
- We will use trigonometric ratios to determine the distance between boat and the edge of the cliff, using tangent function.
tan ( θ ) = H / B
B = H / tan ( θ )
B = 235 / tan ( 21 )
B = 612.2 ft
angle x would end up being equal to 71 degrees.
Proving a relation for all natural numbers involves proving it for n = 1 and showing that it holds for n + 1 if it is assumed that it is true for any n.
The relation 2+4+6+...+2n = n^2+n has to be proved.
If n = 1, the right hand side is equal to 2*1 = 2 and the left hand side is equal to 1^1 + 1 = 1 + 1 = 2
Assume that the relation holds for any value of n.
2 + 4 + 6 + ... + 2n + 2(n+1) = n^2 + n + 2(n + 1)
= n^2 + n + 2n + 2
= n^2 + 2n + 1 + n + 1
= (n + 1)^2 + (n + 1)
This shows that the given relation is true for n = 1 and if it is assumed to be true for n it is also true for n + 1.
<span>By mathematical induction the relation is true for any value of n.</span>