Ejercicio 255

Ejercicio 255

1. –16 × –25 = ( –1 ) ( 4 2 ) × ( –1 ) ( 5 2 ) =4 –1 × 5 ( –1 ) 5 =20 ( –1 ) 2 =–20
2. –81 × –49 = ( –1 ) ( 9 2 ) × ( –1 ) ( 7 2 ) =9 –1 × 7 –1 =63 ( –1 ) 2 =–63
3. 5 –36 × 4 –64 =5 ( –1 ) ( 6 2 ) × 4 ( –1 ) ( 8 2 ) =5 × 6 –1 × 4 × 8 –1 =960 ( –1 ) 2 =–960
4. –3 × –2 = ( –1 ) ( 3 ) × ( –1 ) ( 2 ) =3 –1 × 2 –1 =6 ( –1 ) 2 =–6
5. 2 –5 × 3 –7 =2 ( –1 ) ( 5 ) × 3 ( –1 ) ( 7 ) =2 –1 5 × 3 –1 7 =6 35 ( –1 ) 2 =–6 35
6. –3 × –75 = ( –1 ) ( 3 ) × ( –1 ) ( 3 ) ( 5 2 ) = –1 3 × 5 –1 3 =5 ( –1 ) 2 ( 3 ) 2 =–15
7. 2 –7 × 3 –28 =2 ( –1 ) ( 7 ) × 3 ( –1 ) ( 2 2 ) ( 7 ) =2 –1 7 × 3 × 2 –1 7 =12 ( –1 ) 2 ( 7 ) 2 =–84
8. –49 × –4 × –9 = ( –1 ) ( 7 2 ) × ( –1 ) ( 2 2 ) × ( –1 ) ( 3 2 ) =7 –1 × 2 –1 × 3 –1 =42 ( –1 ) 3 =42 ( –1 ) 2 ( –1 ) =–42i
9. –2 × 3 –5 × –10 = ( –1 ) ( 2 ) × 3 ( –1 ) ( 5 ) × ( –1 ) ( 5 ) ( 2 ) = –1 2 × 3 –1 5 × –1 5 2 =3 ( –1 ) 3 ( 5 ) 2 ( 2 ) 2 =3( 5 ) ( 2 ) ( –1 ) 2 ( –1 ) =–30i
10. –12 × –27 × –8 × –50 = ( –1 ) ( 2 2 ) ( 3 ) × ( –1 ) ( 3 2 ) ( 3 ) × ( –1 ) ( 2 2 ) ( 2 ) × ( –1 ) ( 5 2 ) ( 2 ) =2 –1 3 × 3 –1 3 × 2 –1 2 × 5 –1 2 =2 × 3 × 2 × 5 ( 3 ) 2 ( 2 ) 2 =60( 3 ) ( 2 ) =360
11. –5 –x × 3 –y =–5 ( –1 ) ( x ) × 3 ( –1 ) ( y ) =–5 –1 x × 3 –1 y =15 ( –1 ) 2 xy =–15 xy
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