Bytelearn - cat image with glassesAI tutor

Welcome to Bytelearn!

Let’s check out your problem:

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

P(x)=-15 x(x-8)
What is the maximum power possible?
watts

The power generated by an electrical circuit (in watts) as a function of its current xx (in amperes) is modeled by\newlineP(x)=15x(x8)P(x)=-15x(x-8)\newlineWhat is the maximum power possible?\newlinewatts

Full solution

Q. The power generated by an electrical circuit (in watts) as a function of its current xx (in amperes) is modeled by\newlineP(x)=15x(x8)P(x)=-15x(x-8)\newlineWhat is the maximum power possible?\newlinewatts
  1. Analyzing Quadratic Function: To find the maximum power possible, we need to analyze the quadratic function P(x)=15x(x8)P(x) = -15x(x - 8). This is a parabola that opens downwards because the coefficient of x2x^2 is negative (15-15). The maximum value of this function occurs at the vertex of the parabola.
  2. Finding Vertex: The vertex of a parabola given by the function f(x)=ax2+bx+cf(x) = ax^2 + bx + c is at the point (h,k)(h, k), where h=b2ah = -\frac{b}{2a}. In our case, the function P(x)=15x2+120xP(x) = -15x^2 + 120x can be written in the form ax2+bx+cax^2 + bx + c by expanding the given expression.
  3. Expanding Function: Expanding P(x)=15x(x8)P(x) = -15x(x - 8) gives us P(x)=15x2+120xP(x) = -15x^2 + 120x. Here, a=15a = -15 and b=120b = 120. There is no cc term, so c=0c = 0.
  4. Calculating x-coordinate: Using the formula for the vertex h=b2ah = -\frac{b}{2a}, we substitute a=15a = -15 and b=120b = 120 to find the x-coordinate of the vertex.h=120215=12030=4h = -\frac{120}{2 \cdot -15} = -\frac{120}{-30} = 4.
  5. Substitute xx into Function: The xx-coordinate of the vertex is 44. To find the yy-coordinate, which is the maximum power, we substitute x=4x = 4 back into the function P(x)P(x).\newlineP(4)=15×4×(48)P(4) = -15 \times 4 \times (4 - 8).
  6. Calculate Maximum Power: Calculate P(4)=15×4×(48)=15×4×4=15×16=240P(4) = -15 \times 4 \times (4 - 8) = -15 \times 4 \times -4 = -15 \times 16 = -240.

More problems from Find the roots of factored polynomials