4-mashq. Quyidagilarning har biri uchun javob musbat yoki manfiy bo‘lishini aniqlang, so‘ng ularni kalkulyatorsiz yoki algebraik tugmalarsiz hisoblang: a) (−16) + (−14); b) 17 + (−9); d) −13 + 21; e) (−23) + 12; f) 0 + (−25); g) 14 + (−26).

Topshiriq tarjimasi: Har bir yig‘indining musbat yoki manfiy bo‘lishini aniqlang, so‘ng hisoblang.

1. a) Ikkala qo‘shiluvchi manfiy, shuning uchun yig‘indi manfiy: \((-16)+(-14)=-(16+14)=-30\).
2. b) Musbat sonning moduli kattaroq: \(17>9\). Yig‘indi musbat: \(17+(-9)=17-9=8\).
3. d) Musbat sonning moduli kattaroq: \(21>13\). Yig‘indi musbat: \(-13+21=21-13=8\).
4. e) Manfiy sonning moduli kattaroq: \(23>12\). Yig‘indi manfiy: \((-23)+12=-(23-12)=-11\).
5. f) Nol sonni o‘zgartirmaydi: \(0+(-25)=-25\), manfiy.
6. g) Manfiy sonning moduli kattaroq: \(26>14\). Yig‘indi manfiy: \(14+(-26)=-(26-14)=-12\).

Javob: a) −30 (manfiy); b) 8 (musbat); d) 8 (musbat); e) −11 (manfiy); f) −25 (manfiy); g) −12 (manfiy).