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Determine the function f(x)= kx+m if f(x-1)-f(x)=2 and f(-2)=1-m

User Selllikesybok
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1 Answer

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f(x) = kx + m \\ f(x - 1) = k(x - 1) + m


f(x - 1) - f(x) = 2 \\ k(x - 1) + m - kx - m = 2 \\ kx - k + m - kx - m = 2 \\ - k = 2 \\ k = 2


f( - 2) = k( - 2) + m = 1 - m \\ k( - 2) + m = 1 - m \\ ( - 2)( - 2) + m = 1 - m \\ 4 + m = 1 - m \\ 2m = - 3 \\ m = ( - 3)/(2)


f(x) = - 2x - (3)/(2)

User Rwsimmo
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