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3 Zadania zamkniete w załączniku. Prosze o pomoc.

3 Zadania Zamkniete W Załączniku Prosze O Pomoc class=

Odpowiedź :

Poziomka777viz

Odpowiedź:

3]

a= 0,4              b= -  3      a*b= -3*0,4=- 1,2

4]

(1/3  x  +3y)²= 1/9  x²+ 2*1/3  x  *3y  +9y²= 1/9  x²+2 xy  +9y²

wpisz 2 xy

5]

A= (3√3)²-(2√2)²= 27-8=19 >0

B= 20+ 54- 12√30= 74-12√30 >0

C=(7√2)²-(5√3)²= 98-75=23>0

odp. D musi byc poprawna i = (3√3-5√5)(3√3+5√5)=(3√3)²-(5√5)²=

27-125= - 98

Szczegółowe wyjaśnienie:

Basetlaviz

3.

[tex]a = \sqrt[4]{0,0256} = 0,4\\\\b = \sqrt[7]{-2187} = -3\\\\a\cdot b = 0,4\cdot(-3) = -1,2\\\\\boxed{a\cdot b = -1,2}\\\\\underline{Odp. \ C}[/tex]

4.

[tex]\frac{1}{9}x^{2} + ... + 9y^{2} = (\frac{1}{3}+3y)^{2} = \frac{1}{9}x^{2}+2xy+9y^{2}\\\\\boxed{Odp. \ A. \ 2xy}[/tex]

5.

[tex]A) \ (3\sqrt{3}-2\sqrt{2})(3\sqrt{3}+2\sqrt{2}) =(3\sqrt{3})^{2}-(2\sqrt{2})^{2} = 27-8 = 19\\\\B) \ (2\sqrt{5}-3\sqrt{6})^{2} = (2\sqrt{5})^{2}-2\cdot2\sqrt{5}\cdot3\sqrt{6}+(3\sqrt{6})^{2} = 20-12\sqrt{30}+54 = 74-12\sqrt{30}\\\\C) \ (7\sqrt{2}-5\sqrt{3})(7\sqrt{2}+5\sqrt{3} )=(7\sqrt{2})^{2}-(5\sqrt{3})^{2} = 98-75 = 23\\\\D) \ (3\sqrt{3}-5\sqrt{5})(5\sqrt{5}+3\sqrt{3}) = (3\sqrt{3})^{2}-(5\sqrt{5})^{2} = 27-125 = \boxed{-98}\\\\Odp. \ D.[/tex]