The area of the region enclosed by the curves y=exy = e^x, y=∣ex−1∣y = |e^x - 1|, and the yy -axis is:

Answer: 1−ln⁡21 - \ln 2

Step-by-step solution

Step 1: Analyze the curves and region

We need to find the area enclosed by three curves: y=exy = e^x, y=∣ex−1∣y = |e^x - 1|, and the yy -axis (x=0x=0). First, let's understand the behavior of the function y=∣ex−1∣y = |e^x - 1|.

Step 2: Define the absolute value function

The absolute value function y=∣ex−1∣y = |e^x - 1| can be split into two cases. When ex−1≥0e^x - 1 \ge 0, which means x≥0x \ge 0, the function is y=ex−1y = e^x - 1. When ex−1<0e^x - 1 < 0, which means x<0x < 0, the function is y=−(ex−1)=1−exy = -(e^x - 1) = 1 - e^x.

Step 3: Identify intersection points

We need to find the intersection points of the curves. The yy -axis is x=0x=0. At x=0x=0, y=e0=1y=e^0=1 and y=∣e0−1∣=∣1−1∣=0y=|e^0-1|=|1-1|=0. The curves y=exy=e^x and y=1−exy=1-e^x intersect when ex=1−exe^x = 1-e^x, which gives 2ex=12e^x=1, so ex=1/2e^x=1/2. This means x=ln⁡(1/2)=−ln⁡2x = \ln(1/2) = -\ln 2. At this point, y=1/2y=1/2. The curves y=exy=e^x and y=ex−1doy=e^x-1 do not intersect.

Step 4: Set up the integral for the area

The region is bounded by x=0x=0 on the right. The intersection point of y=exy=e^x and y=1−exy=1-e^x is at x=−ln⁡2x = -\ln 2. For x<0x < 0, ex>1−exe^x > 1-e^x. For x>0x > 0, ex>ex−1e^x > e^x-1. The area is split into two parts: from x=−ln⁡2x = -\ln 2 to x=0x = 0. In the interval [−ln⁡2,0][-\ln 2, 0], the upper curve is y=exy=e^x and the lower curve is y=1−exy=1-e^x. For x≥0x \ge 0, the curve y=∣ex−1∣y=|e^x-1| becomes y=ex−1y=e^x-1. The region is bounded by y=exy=e^x, y=ex−1y=e^x-1 and x=0x=0. However, y=exy=e^x is always above y=ex−1y=e^x-1, and the yy -axis is x=0x=0. The area for x≥0x \ge 0 is not enclosed by the three given curves. Thus, the area is only from x=−ln⁡2x = -\ln 2 to x=0x = 0.

Step 5: Evaluate the integral

Now we evaluate the definite integral. We integrate (2ex−1)(2e^x - 1) from x=−ln⁡2x = -\ln 2 to x=0x = 0. The antiderivative of 2ex−12e^x - 1 is 2ex−x2e^x - x. Plugging in the limits, we get (2e0−0)−(2e−ln⁡2−(−ln⁡2))(2e^0 - 0) - (2e^{-\ln 2} - (-\ln 2)). Since e0=1e^0 = 1 and e−ln⁡2=eln⁡(1/2)=1/2e^{-\ln 2} = e^{\ln(1/2)} = 1/2, the expression simplifies to (2−0)−(2⋅1/2+ln⁡2)=2−(1+ln⁡2)=1−ln⁡2(2 - 0) - (2 \cdot 1/2 + \ln 2) = 2 - (1 + \ln 2) = 1 - \ln 2.

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