Aspire's Library

A Place for Latest Exam wise Questions, Videos, Previous Year Papers,
Study Stuff for MCA Examinations - NIMCET

Previous Year Question (PYQs)



Let $ P_1 : y = 4x^2 $ and $ P_2 : y = x^2 + 27 $ be two parabolas. If the area of the bounded region enclosed between $ P_1 $ and $ P_2 $ is six times the area of the bounded region enclosed between the line $ y = ax,; a > 0 $ and $ P_1 $, then $ a $ is equal to:





Solution


Area bounded between $ P_1 $ & $ P_2 $ is

$ \int_{-3}^{3} ((x^2 + 27) - 4x^2),dx $

$ = 2 \int_0^3 (27 - 3x^2),dx = 2[27x - x^3]_0^3 $

$ = 2(81 - 27) = 108 $

$\therefore$ Area between $ P_1 $ & $ L $ is $ 18 $ sq. units

[Image used in solution — second graph]

Area between $ x^2 = 4ay $ and $ x = ay $ is

$ \frac{8a^2}{3m^3} $

$ \therefore \frac{(1/16)^2}{3(1/\alpha)^3} = 18 $

$ \Rightarrow \frac{8}{16 \cdot 16} \cdot \frac{\alpha^3}{3} = 18 $

$ \Rightarrow \alpha = 12 $


Online Test Series,
Information About Examination,
Syllabus, Notification
and More.

Click Here to
View More


Online Test Series,
Information About Examination,
Syllabus, Notification
and More.

Click Here to
View More

Ask Your Question or Put Your Review.

loading...