Question

☆COROANA ☆!!
la ex : 10 va rooog e urgent!!!!.

Answer 1

a) 1/9 + 1/4 = 13/36
b) 2-3/8:1= 2-3/8= 13/8
c) 1- (-36/49) x 49 = 1+36 *49 cu 49 se simplifica* = 37
Pe restul incearca sa le faci tu ;). Sunt destul de simple si trebuie sa exersezi!

Answer 2

10. a) $3^{-2}+ 4^{-2}= \frac{1}{ 3^{2} }+ \frac{1}{ 4^{2} } = \frac{1}{9}+ \frac{1}{16}= \frac{16+9}{144}= \frac{25}{144}$ ≈ 0.173611 

b) $2- \frac{3}{8}:(17-4 ^{2} )=2- \frac{3}{8}:(17-16)=2- \frac{3}{8}:1=2- \frac{3}{8} = \frac{16-3}{8} = \frac{13}{8}$ ≈ $1 \frac{5}{8}$; ≈ 1.625

c) $1^{-2}-(- \frac{6}{7}) ^{2}*49= 1-49* (-\frac{6}{7}) ^{2}= 1-49* (\frac{6}{7}) ^{2}= 1-49* \frac{36}{49}=$$1-36=-(36-1)=-35$

d) $(- \frac{1}{5} )^{-2}-7 ^{2}=(-5) ^{2} -49=25-49=-(49-25)=-24$

e) $1.7 ^{2} -0.3 ^{2} = (\frac{17}{10}) ^{2} -( \frac{3}{10}) ^{2}= \frac{289}{100}- \frac{9}{100}= \frac{289-9}{100}= \frac{280}{100}= \frac{14}{5}$ ≈$2 \frac{4}{5}$; 2.8

f)  $0.5 ^{2}- 3^{2}+ 0.2^{2} =( \frac{1}{2}) ^{2} -9+ (\frac{1}{5}) ^{2}= \frac{1}{4} -9+ \frac{1}{25}= \frac{25-900+4}{100}= \frac{-871}{100}=$$- \frac{871}{100}$ ≈ $-8 \frac{71}{100}$; ≈ -8.71

g) $(- \frac{2}{4}) ^{-1}+3 ^{3} - 1^{3}=(- \frac{1}{2}) ^{-1}+27-1=-2+27-1=-3+27=24$

h) $( \frac{1}{2}) ^{3} -0.5 ^{3} + 1^{-10}=( \frac{1}{2}) ^{3} -( \frac{1}{2}) ^{3} +1=1$

i) $25-25:(- \frac{3}{5}) ^{-2} = 25-25:( \frac{3}{5}) ^{-2}=25-25:( \frac{5}{3}) ^{2}=25-25:\frac{25}{9}$$=25-25* \frac{9}{25}=25-9=16$