Упр.23 ГДЗ Колягин Ткачёва 9 класс (Алгебра)

1) (1,3)^(-118)·(1,3)^127; 2) (0,87)^(-74):(0,87)^(-80);
3) (17/19)^(-47):(17/19)^(-51); 4) (23/21)^56·(23/21)^(-52).

1. $$\left(1{,}3\right)^{-118}\cdot \left(1{,}3\right)^{127}=\left(1{,}3\right)^{-118+127}=\left(1{,}3\right)^9\approx 10{,}60.$$

2. $$\left(0{,}87\right)^{-74}:\left(0{,}87\right)^{-80}=\left(0{,}87\right)^{-74-(-80)}=\left(0{,}87\right)^6\approx 0{,}43.$$

3. $$\left(\frac{17}{19}\right)^{-47}:\left(\frac{17}{19}\right)^{-51}=\left(\frac{17}{19}\right)^{-47-(-51)}=\left(\frac{17}{19}\right)^4\approx 0{,}64.$$

4. $$\left(\frac{23}{21}\right)^{56}\cdot \left(\frac{23}{21}\right)^{-52}=\left(\frac{23}{21}\right)^{56+(-52)}=\left(\frac{23}{21}\right)^4\approx 1{,}44.$$

Ответ

1) 10,60; 2) 0,43; 3) 0,64; 4) 1,44.