Question

Помогите пожалуйста !!! см. фото

Answer 1

а)
${46}^{2} - 92 times 31 + {31}^{2} = {46}^{2} - 2 times 46 times 31 + {31}^{2} = {(46 - 31)}^{2} = {15}^{2} = 225$
b)
$frac{ {37}^{2} - {23}^{2} }{ {47}^{2} - 169 } = frac{ {37}^{2} - {23}^{2} }{ {47}^{2} - {13}^{2} } = frac{(37 - 23)(37 + 23)}{(47 - 13)(47 + 13)} = frac{14 times 60}{34 times 60} = frac{7}{17}$
c)
$frac{ {26}^{3} + {17}^{3} }{ {26}^{2} - 26 times 17 + {17}^{2} } = frac{(2 6 + 17)( {26}^{2} - 26 times 17 + {17}^{2} )}{ {26}^{2} - 26 times 17 + {17}^{2} } = 26 + 17 = 43$
d)
$frac{ {45}^{3} - {25}^{3} }{20} + 45 times 25 = frac{(45 - 25)( {45}^{2} + 45 times 25 + {25}^{2}) }{20} + 45 times 25 = frac{20( {45}^{2} + 45 times 25 + {25}^{2}) }{20} + 45 times 25 = {45}^{2} + 45 times 25 + {25}^{2} + 45 times 25 = {45}^{2} + 2 times 4 5times 25 + {25}^{2} = {(45 + 25)}^{2} = {70}^{2} = 4900$
e)
$frac{ {49}^{2} + {22}^{2} - {29}^{2} - {2}^{2} }{ {65}^{2} - 130 times 45 + {45}^{2} } = frac{(49 - 29)(49 + 29) + (22 - 2)(22 + 2)}{ {65}^{2} - 2 times 65 times 45 + {45}^{2} } = frac{20 times 78 + 20 times 24}{ {(65 - 45)}^{2} } = frac{20(78 + 24)}{ {20}^{2} } = frac{102}{20} = frac{51}{10} = 5 frac{1}{10}$

Answer 2

спасибо <З