If the area of the blue region bounded by the graph and its image after the transformation matrix presented by can be expressed as , where are positive integers and , input as your answer.
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First, I think the picture isn't quite right in that it was horizontally reflected.
Ok, let's get to the solution.
Step 1: Find the equation of the transformed graph x ′ = 2 x + y y ′ = 3 x + 2 y
The original equation: y = x 2
The transformed graph: 3 x + 2 y = ( 2 x + y ) 2
Step 2: Solve for points of intersection between these two graphs via simultaneous equations y = x 2 3 x + 2 y = ( 2 x + y ) 2 Which is relatively straightforward, giving us 4 coordinates: ( 0 , 0 ) , ( − 3 , 9 ) , ( 2 − 1 + ( 5 ) , 2 3 − ( 5 ) ) , ( 2 − 1 − ( 5 ) , 2 3 + ( 5 ) )
Step 3: Make y the subject in the equation of the transformed graph y = − 2 x ± 1 − x + 1
Step 4: Find multiples areas, which will be added/subtracted with each other to find the final area
Let the final area be X
Let A,B,C,D be these areas A = ∫ − 3 2 − 1 − 5 x 2 d x B = ∫ 2 − 1 − 5 0 − 2 x − 1 − x + 1 d x --> chose minus because looking at the lower curve C = ∫ 0 2 − 1 + 5 x 2 d x D = ∫ − 3 2 − 1 + 5 − 2 x + 1 − x + 1 d x --> chose plus because looking at the upper curve
Evaluating all 4 of these, we get A = 3 2 5 − 5 , B = 3 4 + 5 , C = 3 − 2 + 5 , D = 3 5 0 + 5
Step 5: Calculate the final area X = D − A − B − C = 3 2 3