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2.

Determine the area of the region bounded by the curves x=1, y = x - 2 and y2= x.

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To find the area bounded by the curves x=1x = 1, y=x−2y = x - 2, and y2=xy^2 = x:

  1. Points of Intersection:

    • Intersection of y=x−2y = x - 2 (or x=y+2x = y + 2) and y2=xy^2 = x:
      y2=y+2  ⟹  y2−y−2=0  ⟹  (y−2)(y+1)=0y^2 = y + 2 \implies y^2 - y - 2 = 0 \implies (y - 2)(y + 1) = 0
      So, y=−1y = -1 and y=2y = 2.
      For y=−1y = -1, x=1x = 1, which gives the point (1,−1)(1, -1).
      For y=2y = 2, x=4x = 4, which gives the point (4,2)(4, 2).
    • Intersection of x=1x = 1 and y2=xy^2 = x:
      y2=1  ⟹  y=±1y^2 = 1 \implies y = \pm 1, giving points (1,1)(1, 1) and (1,−1)(1, -1).
    • Intersection of x=1x = 1 and y=x−2y = x - 2:
      y=1−2=−1y = 1 - 2 = -1, giving the point (1,−1)(1, -1).
  2. Setting up the Area Integral:
    The bounded region lies between y=−1y = -1 and y=2y = 2:

    • From y=−1y = -1 to y=1y = 1, the region is bounded on the right by x=y+2x = y + 2 and on the left by x=1x = 1.
    • From y=1y = 1 to y=2y = 2, the region is bounded on the right by x=y+2x = y + 2 and on the left by the parabola x=y2x = y^2.

    Area A=∫−11((y+2)−1) dy+∫12((y+2)−y2) dy\text{Area } A = \int_{-1}^{1} ((y + 2) - 1) \, dy + \int_{1}^{2} ((y + 2) - y^2) \, dy
    A=∫−11(y+1) dy+∫12(y+2−y2) dyA = \int_{-1}^{1} (y + 1) \, dy + \int_{1}^{2} (y + 2 - y^2) \, dy

  3. Evaluating the Integrals:
    A1=[y22+y]−11=(12+1)−(12−1)=2A_1 = \left[ \frac{y^2}{2} + y \right]_{-1}^{1} = \left( \frac{1}{2} + 1 \right) - \left( \frac{1}{2} - 1 \right) = 2
    A2=[y22+2y−y33]12=(42+4−83)−(12+2−13)=(6−83)−(136)=103−136=76A_2 = \left[ \frac{y^2}{2} + 2y - \frac{y^3}{3} \right]_{1}^{2} = \left( \frac{4}{2} + 4 - \frac{8}{3} \right) - \left( \frac{1}{2} + 2 - \frac{1}{3} \right) = \left( 6 - \frac{8}{3} \right) - \left( \frac{13}{6} \right) = \frac{10}{3} - \frac{13}{6} = \frac{7}{6}

    Total Area A=2+76=196 square units\text{Total Area } A = 2 + \frac{7}{6} = \frac{19}{6} \text{ square units}

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