Question Simplify the expression 125−75x+15x2−x3 Evaluate (5−x)3Use (a−b)3=a3−3a2b+3ab2−b3 to expand the expression 53−3×52x+3×5x2−x3Solution 125−75x+15x2−x3 Show Solution Find the roots x=5 Evaluate (5−x)3To find the roots of the expression,set the expression equal to 0 (5−x)3=0The only way a power can be 0 is when the base equals 0 5−x=0Move the constant to the right-hand side and change its sign −x=0−5Removing 0 doesn't change the value,so remove it from the expression −x=−5Solution x=5 Show Solution
Algebra
Calculus
Trigonometry
Matrix Algebra Calculus Trigonometry Matrix