xxQueenPxx1706 xxQueenPxx1706 11-03-2024 Mathematics contestada Consider the function f:R->R defined by f(x)=4x²-3x+8. For x>=1 , by the triangle inequality, we observe that |f(x)|=|4x²-3x+8| <=4x²+3x+8 <=4x²+3x²+8x²=15x²