Question

Determine a função f(x)=ax+b e f(1/2)=2 , f(-1)=3 , determine f(-3).

Answer 1

Resposta:

f(1/2)= ax+b

2= 1/2a+b

1/2a+b= 2

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f(-1)= -a+b

-a+b= 3

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1/2a+b= 2

-a+b= 3 *(-1)

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1/2a+b= 2

a -b= -3

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1/2a+a= -1

1a+2a= -2

3a= -2

a= -2/3

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-a+b= 3

2/3+b= 3

2b+3b= 9

5b= 9

b= 9/5

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f(x)= -2/3x+9/5

f-3)= -2/3*(-3)+9/5

f(-3)= 6/3+9/5

f(-3)= 2+9/5

f(-3)= 10+9/5

f(-3)= 19/5