# Ex 8.2, 5

Last updated at May 29, 2018 by Teachoo

Last updated at May 29, 2018 by Teachoo

Transcript

Ex 8.2 , 5 Using integration find the area of the triangular region whose sides have the equations 𝑦=2𝑥+1, 𝑦=3𝑥+1 and 𝑥=4 Step 1: Draw the figure & x = 4 Required Area = Area ABC Finding point of Intersection B & C For B B is intersection of y = 3x + 1 & x = 4 Putting x = 4 in y = 3x + 1 y = 3(4) + 1 = 13 So, B(4, 13) For C C is intersection of y = 2x + 1 & x = 4 Putting x = 4 in y = 2x + 1 y = 2(4) + 1 = 9 So, C(4, 9) Finding Area Required Area ABC = Area OABD – Area OACD Area OABD Area OABD = 04𝑦 𝑑𝑥 where y = 3x + 1 = 2 ×422+4− 2 × 022+0 = 16 + 4 − 0 = 20 Area Required = Area ABDO − Area ACDO = 28 − 20 = 8 unit2

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Davneet Singh

Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.