contestada

What is the exact value for the expression the square root of 189. − the square root of 21. + the square root of 84.? Simplify if possible.

Respuesta :

irspow
√189-√21+√84

√(3*3*3*7)-√(3*7)+√(2*2*3*7)  now if you remove the perfect squares...

3√21-√21+2√21

(3-1+2)√21

4√21  

Answer:

the exact value of the given expression is:[tex]4\sqrt{21}[/tex]

Step-by-step explanation:

we are given to find the value of the expression

square root of 189-square root of 21+square root of 84

[tex]\sqrt{189} =\sqrt{3\times3\times3\times7}[/tex]

[tex]\sqrt{189}=3\sqrt{21}[/tex]

similarly  [tex]\sqrt{84}=\sqrt{2\times2\times3\times7}=2\sqrt{21}[/tex]

therefore [tex]\sqrt{189} -\sqrt{21}+\sqrt{84} =3\sqrt{21}-\sqrt{21}+2\sqrt{21}[/tex]

                                                                     [tex]=4\sqrt{21}[/tex]

hence the resultant answer corresponding to the given expression is [tex]4\sqrt{21}[/tex].

Otras preguntas