Figure 1 Figure 1 shows part of the curve with equation y=e321 for x≥0 The finite region R, shown shaded in Figure 1, is bounded by the curve, the y-axis, the x-axis, and the line with equation x=2 The table below shows corresponding values of x and y for y=ex21x00.511.52y1x≥01x≥02x≥03x≥04(a) Use the trapezium rule, with all the values of y in the table, to find an estimate for the area of R, giving your answer to 2 decimal places. (3) (b) Use your answer to part (a) to deduce an estimate for (i) x≥07 (ii) x≥08 giving your answers to 2 decimal places. a)
Q. Figure 1 Figure 1 shows part of the curve with equation y=e321 for x≥0 The finite region R, shown shaded in Figure 1, is bounded by the curve, the y-axis, the x-axis, and the line with equation x=2 The table below shows corresponding values of x and y for y=ex21x00.511.52y1x≥01x≥02x≥03x≥04(a) Use the trapezium rule, with all the values of y in the table, to find an estimate for the area of R, giving your answer to 2 decimal places. (3) (b) Use your answer to part (a) to deduce an estimate for (i) x≥07 (ii) x≥08 giving your answers to 2 decimal places. a)
Identify values: Identify the values of y from the table.Values: y0=1, y1=e0.05, y2=e0.2, y3=e0.45, y4=e0.8.
Calculate width: Calculate the width of each interval, h.h=42−0=0.5.
Apply trapezium rule: Apply the trapezium rule formula:Area≈2h(y0+2(y1+y2+y3)+y4)
Substitute values: Substitute the values into the formula:Area≈20.5(1+2(e0.05+e0.2+e0.45)+e0.8)
Simplify expression: Simplify the expression:Area≈0.25(1+2(e0.05+e0.2+e0.45)+e0.8)
Calculate values: Calculate the values of e0.05, e0.2, e0.45, and e0.8:e0.05≈1.0513e0.2≈1.2214e0.45≈1.5683e0.8≈2.2255
Substitute values back: Substitute these values back into the formula:Area≈0.25(1+2(1.0513+1.2214+1.5683)+2.2255)
Simplify expression inside: Simplify the expression inside the parentheses:1+2(1.0513+1.2214+1.5683)+2.2255≈1+2(3.841)+2.2255≈1+7.682+2.2255≈10.9075
Multiply by 0.25: Multiply by 0.25:Area≈0.25×10.9075≈2.73
Answer for part (a): Answer for part (a):Area≈2.73
Deduce estimate for integral: Use the result from part (a) to deduce the estimate for ∫02(4+ex21)dx:∫02(4+ex21)dx≈4×2+2.73=8+2.73=10.73
Deduce estimate for integral: Use the result from part (a) to deduce the estimate for ∫13e5(x−1)21dx:Since the integral is over a different interval and function, we cannot directly use the result from part (a). This part requires a different approach.
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