Practicing Success
If $8+2 p x^2-36 x-27^3=(2-3 x)^3$, then what is the value of p ? |
27 54 9 -27 |
27 |
8 + 2px2 – 36x – 27x3 = (2 – 3x)3 (a – b)3 = a3 – b3 – 3ab(a – b) (2 – 3x)3 = (2)3 – (3x)3 – 3 × 2 × 3x (2 – 3x) = 8 – 27x3 – 18x (2 – 3x) = 8 – 27x3 – 36x + 54x2 Comparison the coefficient of both the equation, we get 8 + 2px2 – 36x – 27x3 = 8 – 27x3 – 36x + 54x2 = 2px2 = 54x2 = 2p = 54 = p = 27 |