Question
If 9x² + y² = 37 and xy=2, x, y>0, then the
value of (27x³ + y³) is:Solution
27x3 + y3 = (3x + y) (9x2 + y2 – 3xy) = use (a + b)2 = a2 + b2 + 2ab = (3x + y)2 = ax2 + y2 + 6xy = (3x + y)2 = 37 + 6 × 2 = 49 = 3x + y = 7 = 27x3 + y3 = 7 × (37 – 3 × 2) = 27x3 + y3 = 7 × 31 = 217
More Algebra Questions
Internet Explorer is a _______ ?
Main function of CPU is
Symbols A-F are used in which one of the following ?
In a Computer a byte generally consists of :
In Windows computer, the deleted files are transferred to
The shortcut for switching to next worksheet window in Excel is:
Shortcut Key for Multiple Tab -
Which function key is used to refresh the screen?
To move from one worksheet to another in MS Excel, you should click on the:Â Â
Holding down the Shift key while typing letters will result in______?
