Question

Va rog repede! Exercițiul poate fi efectuat si pe un caiet! Dau coruana! Decat ex 3

Answer 1

Răspuns:

Explicație pas cu pas:

a = -7/3

b = 1/5

c = -3/2

a)

a - b + c = -7/3 - 1/5 - 3/2 = -70/30 - 6/30 - 45/30 = -121/30

(-121/30)*30/11 = -121/11 = -11

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b)

(a + b - c)^2 = (-7/3 + 1/5 + 3/2)^2 = (-70/30 + 6/30 + 45/30)^2 = (-19/30)^2

= 361/900

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c)

10/3*(-19/30) = -19/9

Answer 2

Răspuns:

Explicație pas cu pas:

a = - 7/3,   b = 1/5,   c = - 3/2

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a)  

( a - b + c ) × 2 intregi si 8/11 =

-> introducem intregii in fractie

2 intregi si 8/11 = ( 2×11+8)/11 = 30/11

______________________________

= ( - 7/3 - 1/5 - 3/2) × 30/11 = - 11

→  aflam cel mai mic multiplu comun al numitorilor 3, 5 si 2 = 3×5×2 = 30

→ amplific fractia 7/3 cu 10 = (7×10)/(3×10) = 70/30

  amplific fractia 1/5 cu 6 = (1×6)/(5×6) = 6/30

  amplific fractia 3/2 cu 15 = (3×15)/(2×15) = 45/30

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= ( - 70/30 - 6/30 - 45/30) × 30/11 =

= ( - 121/30) × 30/11 =

= ( - 121/11) × 30/30 =

= - 11 × 1 =

= - 11

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b)

( a + b - c )² = 361/900

= ( - 7/3 + 1/5 + 3/2 )² =       - ( - 3/2) = + 3/2

= > amplific fractiile cu 10, cu 6 si cu 15, pentru a le aduce la acelasi numitor ( 30)

= ( - 70/30 + 6/30 + 45/30)² =

= ( - 19/30)² =

= 19²/30² =

= 361/900

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c)

3 intregi si 1/3 = ( 3×3+1)/3 = 10/3

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= 10/3 × ( a + b - c ) =

= 10/3 × ( - 7/3 + 1/5 + 3/2) =

= 10/3 × ( - 70/30 + 6/30 + 45/30) =

= 10/3 × ( - 19/30) =

= - 19/9 =

= - 2 intregi si 1/9