Saved Bookmarks
| 1. |
if the zeroes of x2-kx+6 are in the ratio 3:2, find k. |
| Answer» Let roots are {tex}\\alpha \\ and \\ \\beta {/tex}{tex}{\\alpha \\over \\beta } = {3\\over 2}{/tex}=>\xa0{tex}\\alpha ={ 3\\over 2}\\beta{/tex}.....(1)ThenProduct of roots =\xa0{tex}c\\over a{/tex}=>\xa0{tex}\\alpha \\beta = 6{/tex}=>\xa0{tex}{3\\over 2}\\beta \\beta = 6{/tex}=>\xa0{tex}\\beta^2 = 4{/tex}=>\xa0{tex}\\beta = \\pm 2{/tex}Putting in (1) we get{tex}\\alpha = \\pm 3{/tex}Now sum of roots =\xa0{tex}-{b\\over a}{/tex}=> 3 + 2 = k or -3 + (-2) = k\xa0=> k = 5 or k = -5\xa0 | |