Question

ex acord 10 puncte dau coroana​

Answer 1

$a = ({7}^{2} - {2}^{3} \times 5) \times 4 - 11$

$(49 - 8 \times 5) \times 4 - 11 \\ = (49 - 40) \times 4 - 11 = \\ = 9 \times 4 - 11 = \\ = 36 - 11= \\ = 25 = {5}^{2} = > a \: este \: patrat \: \\ perfect$

${8}^{50} + {8}^{51} = {8}^{50} + {8}^{50} \times {8}^{1} = \\ = {8}^{50} \times 1 + {8}^{50} \times 8 = \\ = {8}^{50} \times (1 + 8) = {8}^{50} \times 9 = \\ = ( {8}^{25} \times 3 ) ^{2} = > este \\ patrat \: perfect$

Answer 2

a = ( 7 ^ 2 - 2 ^ 3 × 5 ) × 4 - 11

a = ( 49 - 8 × 5 ) × 4 - 11

a = ( 49 - 40 ) × 4 - 11

a = 9 × 4 - 11

a = 36 - 11

a = 25 = 5 ^ 2 => a = pătrat perfect

b = 8 ^ 50 + 8 ^ 51

b = 8 ^ 50 + 8 ^ 50 × 8 ^ 1

b = 8 ^ 50 × 1 + 8 ^ 50 × 8

b = 8 ^ 50 × ( 1 + 8 )

b = 8 ^ 50 × 9

b = ( 8 ^ 25 × 3 ) ^ 2 => b = pătrat perfect