Question

VA ROG IMI TREBUIE URGENT !!!!
Sa se afle : a) produsul a•b = cand a=√48-√18-√108+√128
b=√162-√75-√32+√147
b) ab-10la2 = daca 3/b=a/32
c) doua numere a si b care sunt direct proportionale cu 2 ai 3 , iar suma patratelor este 52.

Answer 1

b) ab-100=?

3/b=a/32    ⇒ ab=3×32    ⇒ab=96

96 - 100= -4

c) a/2=b/3=k     și   a²+b²=52

a/2=k   ⇒  a=2k

b/3=k   ⇒  b=3k

(2k)²+(3k)²=52

13k²=52

k²=52/13=4

k=√4=2

a=2k=2×2=4

b=3k=3×2=6

Sper că te-am ajutat!

Answer 2

b)

[tex]\it \dfrac{3}{b} = \dfrac{a}{32} \Rightarrow ab= 32\cdot3 \Rightarrow ab=96 \Rightarrow ab-10^2=96-10^2= \\ \\ =96-100=-4[/tex]

c)

[tex]\it \dfrac{a}{2} = \dfrac{b}{3} \Rightarrow \dfrac{a^2}{4} = \dfrac{b^2}{9} =\dfrac{a^2+b^2}{4+9} = \dfrac{52}{13} =4 \\ \\ \\ \dfrac{a^2}{4} =4\Rightarrow a^2=16 \Rightarrow a = 4 \\ \\ \\ \dfrac{b^2}{9} =4\Rightarrow b^2=36 \Rightarrow b = 6 [/tex]