637.07

\(324,82+312,25=637,07\)

\(324,82+312,25=637,07\)

 a) 637,07

b) 17,86

c) -56,63

d) 21,53

a) 324,82+312,25 = 637,07                     

b) (-12,07)+(-5,79)= 17,86

c) (-41,29)-15,34 = -56,63

d) (-22,65)-(-1,12)=  21,53

\(\text{6) 27,693 + 8,54 = 36.233}\)

\(\text{7) (-81,73) - 17,249= -98.979}\)

\(\text{8) 9,371 . 8,65 = 81.05915}\)

\(\text{9) (-14,29) . 73,6 = -1051.744}\)

\(\text{10) 24,108 : 6,15= 3.92}\)

\(\text{11) 324,82 + 312,25= 637.07}\)

\(\text{13) 8,446 : 4,12= 2.05}\)

\(\text{14) (-882) : 3,6 = -245}\)

\(\text{15) 19,427 . 1,8 = 34.9686}\)

\(6) 27,693 + 8,54 = 36,233\\ 7) (-81,73)-17,249 = -98,979\\ 8) 9,371.8,65 = 81,05915\\ 9) (-14,29).73,6 = -1051,744\\ 10) 24,108:6,15 = 3,92\\ 11) 324,82+ 312,25 = 637,07\\ 13) 8,446 : 4,12 = 2,05\\ 14) (-882):3,6 = -245\\15) 19,427.1,8 = 34,9686\)

a: sin a=2/3

=>cos^2a=1-(2/3)^2=5/9

=>\(cosa=\dfrac{\sqrt{5}}{3}\)

\(tana=\dfrac{2}{3}:\dfrac{\sqrt{5}}{3}=\dfrac{2}{\sqrt{5}}\)

\(cota=1:\dfrac{2}{\sqrt{5}}=\dfrac{\sqrt{5}}{2}\)

b: cos a=1/5

=>sin^2a=1-(1/5)^2=24/25

=>\(sina=\dfrac{2\sqrt{6}}{5}\)

\(tana=\dfrac{2\sqrt{6}}{5}:\dfrac{1}{5}=2\sqrt{6}\)

\(cota=\dfrac{1}{2\sqrt{6}}=\dfrac{\sqrt{6}}{12}\)

c: cot a=1/tana=1/2

\(1+tan^2a=\dfrac{1}{cos^2a}\)

=>1/cos^2a=1+4=5

=>cos^2a=1/5

=>cosa=1/căn 5

\(sina=\sqrt{1-cos^2a}=\dfrac{2}{\sqrt{5}}\)

a) ta có: A = 2156 + 357

=> A - 357 = 2156 + (357-357)

A - 357 = 2156

=> A - 2156 = (2156-2156) + 357

A - 2156 = 357

b) ta có: B = 9475 - 7436

=> B + 7436 = 9475 - (7436-7436)

B + 7236 = 9475

=> 9475 - B = 9475 + 9475 - 7436

9475 -B = 2.9475 - 7436

( phần b câu 2 hình như bn chép sai)

a)A - 357 = 2156 và A - 2156 = 357

b)B + 7436 = 9475 và 9475 - B = 7436