Given:
The power generated by an electrical circuit (in watts) as a function of its current x (in amperes) is modeled by

To find:
The current which will produce the maximum power.
Solution:
We have,


Differentiate with respect to x.

...(i)
To find the extreme point equate P'(x)=0.


Divide both sides by -30.

Differentiate (i) with respect to x.

(Maximum)
It means, the given function is maximum at x=4.
Therefore, the current of 4 amperes will produce the maximum power.
Since triangle DEF = triangle JKL, m<D = m<J, m<E = m<K, m<F = m<L.
m<F = m<L = 90 degrees
m<K = m<E = 5(m<D)
but m<E + m<D = 90 degrees [right angled triangle]
5(m<D) + m<D = 90 degrees
6(m<D) = 90 degrees
m<D = 90 / 6 = 15 degrees.
Answer:
648
Step-by-step explanation:
You can use a calculator or break it into smaller problems, then add them together