Question

x= 1+3(⅓)+2(⅔ )
find the value of 2x³-6x²-12x+13​

Answer 1

Step-by-step explanation:

$The \: \: value \: \: of \: \: {\large x} \: \: is : \\ 1 + 3 \frac{1}{3} + 2 \frac{2}{3} \\ = 1 + \frac{10}{3} + \frac{8}{3} \\ = \frac{3 + 10 + 8}{3} \\ = \frac{ \cancel{ 21} _{ \: \: \: 7} }{ \cancel 3 _{ \: \: \: 1} } \\ \boxed{ \large x = \underline{ \underline{ \bf 7}}} \\ \\ 2 {x}^{3} - 6 {x}^{2} - 12x + 13 \\ = 2 {(7)}^{3} - 6 {(7)}^{2} - 12(7) + 13 \\ = (2 \times 343) - (6 \times 49) - (12 \times 7) + 13 \\ = 686 - 294 - 84 + 13 \\ = 308 + 13 \\ \boxed{ = \underline{ \underline{ \large \bf 321}}}$