Photo AI

Figure 1 shows part of the curve with equation $x = 4e^{t/3} + 3$ - Edexcel - A-Level Maths Pure - Question 7 - 2013 - Paper 1

Question icon

Question 7

Figure-1-shows-part-of-the-curve-with-equation-$x-=-4e^{t/3}-+-3$-Edexcel-A-Level Maths Pure-Question 7-2013-Paper 1.png

Figure 1 shows part of the curve with equation $x = 4e^{t/3} + 3$. The finite region $R$ shown shaded in Figure 1 is bounded by the curve, the x-axis, the t-axis and... show full transcript

Worked Solution & Example Answer:Figure 1 shows part of the curve with equation $x = 4e^{t/3} + 3$ - Edexcel - A-Level Maths Pure - Question 7 - 2013 - Paper 1

Step 1

Complete the table with the value of $x$ corresponding to $t = 6$, giving your answer to 3 decimal places.

96%

114 rated

Answer

To find the value of xx for t=6t = 6, we plug t=6t = 6 into the equation:

x=4e6/3+3=4e2+3x = 4e^{6/3} + 3 = 4e^2 + 3

Calculating this gives us:

  1. First calculate e27.389e^2 \approx 7.389.
  2. Then, 4×7.38929.5564 \times 7.389 \approx 29.556.
  3. Finally, adding 3 gives x29.556+3=32.556x \approx 29.556 + 3 = 32.556. Therefore, rounded to three decimal places, x32.556x \approx 32.556.

Step 2

Use the trapezium rule with all the values of $x$ in the completed table to obtain an estimate for the area of the region $R$, giving your answer to 2 decimal places.

99%

104 rated

Answer

Using the trapezium rule, the area can be estimated using:

Ah2[y0+2y1+2y2+yn]A \approx \frac{h}{2} [y_0 + 2y_1 + 2y_2 + y_n]

where hh is the width of each interval. Here, h=2h = 2 (intervals between tt values: 0, 2, 4, 6, 8).

Substituting in the values:

A22[3+2(7.107+7.218)+5.223]A \approx \frac{2}{2} [3 + 2(7.107 + 7.218) + 5.223]

Calculating this gives:

A1[3+2(14.325)+5.223]1[3+28.650+5.223]36.873A \approx 1 [3 + 2(14.325) + 5.223] \approx 1 [3 + 28.650 + 5.223] \approx 36.873

Therefore, the area is approximately 36.87 (rounded to 2 decimal places).

Step 3

Use calculus to find the exact value for the area of $R$.

96%

101 rated

Answer

To find the exact area of region RR, we need to calculate the integral:

08(4et/3+3)dt\int_0^8 (4e^{t/3} + 3) \, dt

Calculating each part separately:

  1. The integral of 4et/34e^{t/3} is 12et/312e^{t/3}.
  2. The integral of 3 is 3t3t.

Thus, we can evaluate:

[12et/3+3t]08\left[12e^{t/3} + 3t \right]_0^8

Substituting the limits:

  1. For t=8t = 8: 12e8/3+2412e^{8/3} + 24.
  2. For t=0t = 0: 12e0+0=1212e^0 + 0 = 12.

Thus:

Area=(12e8/3+2412)Area = (12e^{8/3} + 24 - 12)

Calculating gives us the exact area.

Step 4

Find the difference between the values obtained in part (b) and part (c), giving your answer to 2 decimal places.

98%

120 rated

Answer

Let AbA_b be the area from part (b) and AcA_c from part (c). The difference is:

Difference=AbAc\text{Difference} = |A_b - A_c|

Calculate the difference using the approximate area from part (b) and the exact area computed in part (c). Round to two decimal places.

Join the A-Level students using SimpleStudy...

97% of Students

Report Improved Results

98% of Students

Recommend to friends

100,000+

Students Supported

1 Million+

Questions answered

;