A nonlinear function that can be written on the standard form
<span><span>a<span>x2</span>+bx+c,wherea≠0</span><span>a<span>x2</span>+bx+c,wherea≠0</span></span>
is called a quadratic function.
All quadratic functions has a U-shaped graph called a parabola. The parent quadratic function is
Answer:
θ is decreasing at the rate of
units/sec
or
(θ) = 
Step-by-step explanation:
Given :
Length of side opposite to angle θ is y
Length of side adjacent to angle θ is x
θ is part of a right angle triangle
At this instant,
x = 8 ,
= 7
(
denotes the rate of change of x with respect to time)
y = 8 ,
= -14
( The negative sign denotes the decreasing rate of change )
Here because it is a right angle triangle,
tanθ =
-------------------------------------------------------------------1
At this instant,
tanθ =
= 1
Therefore θ = π/4
We differentiate equation (1) with respect to time in order to obtain the rate of change of θ or
(θ)
(tanθ) =
(y/x)
( Applying chain rule of differentiation for R.H.S as y*1/x)
θ
(θ) = 
- 
-----------------------2
Substituting the values of x , y ,
,
, θ at that instant in equation (2)
2
(θ) =
*(-14)-
*7
(θ) = 
Therefore θ is decreasing at the rate of
units/sec
or
(θ) = 
25 × 52% =
25 × 52/100=
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