a. 3√3 - 2√2
b. Ø
c. 3√3 - 4√2
d. 3√3
*Simplify.* √27 - √8 + 2√2?
2009-10-15 3:18 pm
回答 (12)
2009-10-15 3:34 pm
✔ 最佳答案
√27 - √8 + 2√2=√(9*3)-√(4*2)+2√2
=3√3-2√2+2√2
=3√3 answer//
Answer is d.3√3
2009-10-16 12:02 am
3â3.
2009-10-15 10:35 pm
answer is D=3â3
2009-10-15 10:30 pm
We know that â3 and â2 cannot be added or subtracted together. Think of these as x and y. You cannot join x and y together somehow with addition or subtraction to get one term like xy or something, so we have to keep the â3 and the â2 terms separate.
For â27, this can be written as â(3*3*3) = â(3^2)*â3 = 3â3. Since 3^2=9 is a perfect square, and 9 is a factor of 27, we can take the square root of this and leave the 3 still under the radical.
Same goes for â8. This can be written as â(2*2*2) = â(2^2)*2 = 2â2. 2^2=4 is also a perfect square. These (that is, 1, 4, 9, 16, 25, etc are the only factors that can be simplified under a radical).
Now think of â2 as a variable, x. We have the form -2x + 2x = 0. We can add however many of â2 terms together so long as the all have the common factor of â2. Then we have 3â3 - 2â2 + 2â2 = 3â3.
Have fun!
For â27, this can be written as â(3*3*3) = â(3^2)*â3 = 3â3. Since 3^2=9 is a perfect square, and 9 is a factor of 27, we can take the square root of this and leave the 3 still under the radical.
Same goes for â8. This can be written as â(2*2*2) = â(2^2)*2 = 2â2. 2^2=4 is also a perfect square. These (that is, 1, 4, 9, 16, 25, etc are the only factors that can be simplified under a radical).
Now think of â2 as a variable, x. We have the form -2x + 2x = 0. We can add however many of â2 terms together so long as the all have the common factor of â2. Then we have 3â3 - 2â2 + 2â2 = 3â3.
Have fun!
2009-10-15 10:28 pm
â27 - â8 + 2â2
= â(3^2 * 3) - â(2^2 * 2) + 2â2
= 3â3 - 2â2 + 2â2
== 3â3
(answer d)
= â(3^2 * 3) - â(2^2 * 2) + 2â2
= 3â3 - 2â2 + 2â2
== 3â3
(answer d)
2009-10-15 10:26 pm
â27 - â8 + 2â2 = â(3*3*3) - â(2*2*2) + 2â2
. . . . . . . . . . . .= 3â3 - 2â2 + 2â2
. . . . . . . . . . . .= 3â3 . . (option d)
. . . . . . . . . . . .= 3â3 - 2â2 + 2â2
. . . . . . . . . . . .= 3â3 . . (option d)
2009-10-15 10:25 pm
â27 - â8 + 2â2
â27 - 2â2 + 2â2
â27
â9*3
3â3===>(d)
â27 - 2â2 + 2â2
â27
â9*3
3â3===>(d)
2009-10-15 10:23 pm
â27 - â8 + 2â2 = 3â3 - 2â2 + 2â2 = 3â3
a. 3â3 - 2â2
b. Ã
c. 3â3 - 4â2
d. 3â3 ................... correct answer
a. 3â3 - 2â2
b. Ã
c. 3â3 - 4â2
d. 3â3 ................... correct answer
2009-10-15 10:23 pm
â27-â8+2â2
=â9â3-â4â2+2â2
=3â3-2â2+2â2
=3â3.
So, the answer is d.
:-)
=â9â3-â4â2+2â2
=3â3-2â2+2â2
=3â3.
So, the answer is d.
:-)
2009-10-15 10:23 pm
â27= â9*3 = â9*â3
â9 =3
so ,â27 = 3â3
â8 = â4*2 =â4â2 =2â2
â27 - â8 + 2â2 = 3â3 - 2â2+2â2 = 3â2
So answer is 3â3
â9 =3
so ,â27 = 3â3
â8 = â4*2 =â4â2 =2â2
â27 - â8 + 2â2 = 3â3 - 2â2+2â2 = 3â2
So answer is 3â3
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