Q. Three points on the graph of the function f(x) are {(0,1),(1,4),(2,9)}. Which equation represents f(x) ?f(x)=5x−1f(x)=4xf(x)=3x+1f(x)=(x+1)2
Test Option 1: Test the given points with the first option f(x)=5x−1.Substitute x=0 into f(x)=5x−1 to see if it equals 1.f(0)=5(0)−1=−1Since f(0) should equal 1, this option is incorrect.
Test Option 2: Test the given points with the second option f(x)=4x. Substitute x=0 into f(x)=4x to see if it equals 1. f(0)=40=1 This matches the first point (0,1). Now test the second point (1,4). f(1)=41=4 This matches the second point (1,4). Now test the third point (2,9). x=00 Since x=01 should equal x=02, this option is incorrect.
Test Option 3: Test the given points with the third option f(x)=3x+1.Substitute x=0 into f(x)=3x+1 to see if it equals 1.f(0)=3(0)+1=1This matches the first point (0,1). Now test the second point (1,4).f(1)=3(1)+1=4This matches the second point (1,4). Now test the third point (2,9).x=00Since x=01 should equal x=02, this option is incorrect.
Test Option 4: Test the given points with the fourth option f(x)=(x+1)2. Substitute x=0 into f(x)=(x+1)2 to see if it equals 1. f(0)=(0+1)2=1 This matches the first point (0,1). Now test the second point (1,4). f(1)=(1+1)2=4 This matches the second point (1,4). Now test the third point (2,9). x=00 This matches the third point (2,9). Therefore, this option is correct.
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