What is (5-2√7)(√7+2)?
Thanks.
Help with maths please...?
2010-06-12 11:09 am
回答 (8)
2010-06-12 11:15 am
✔ 最佳答案
(5-2√7)(√7+2) =5√7+ 10 - 14 - 4√7=
√7 - 4
2010-06-12 7:27 pm
(5 - 2â7)(â7 + 2)
= 5(â7) + 5(2) - 2â7(â7) - 2â7(2)
= 5â7 + 10 - 2(7) - 4â7
= 10 - 14 + 5â7 - 4â7
= -4 + â7
= 5(â7) + 5(2) - 2â7(â7) - 2â7(2)
= 5â7 + 10 - 2(7) - 4â7
= 10 - 14 + 5â7 - 4â7
= -4 + â7
2010-06-12 6:58 pm
multiply the terms..
we get, sqrt(7)-4
we get, sqrt(7)-4
2010-06-12 6:35 pm
First, times the first number in the first set of brackets by both numbers in the second set of brackets.
5 * â7 = 5â7
5 * 2 = 10
Next, times the second number in the first set of brackets by both numbers in the second set of brackets.
-2â7 * â7 = -2 * â7 * â7 = -2 * 7 = -14
-2â7 * 2 = -4â7
So your answer is:
5â7 + 10 - 14 - 4â7
This can be simplified:
â7 - 4
You would normally leave this as it is, in its "surd form", but it can be further evaluated to get -1.354 to three decimal places.
5 * â7 = 5â7
5 * 2 = 10
Next, times the second number in the first set of brackets by both numbers in the second set of brackets.
-2â7 * â7 = -2 * â7 * â7 = -2 * 7 = -14
-2â7 * 2 = -4â7
So your answer is:
5â7 + 10 - 14 - 4â7
This can be simplified:
â7 - 4
You would normally leave this as it is, in its "surd form", but it can be further evaluated to get -1.354 to three decimal places.
2010-06-12 6:33 pm
=5\/''7'''' +10 -14 -4\/''''7'''''=\/'''7''''' -4
God bless you.
God bless you.
2010-06-12 6:30 pm
(5-2root7)(root7+2)
=> 5(root7+2)-2root7(root7+2)
=> 5root7+10-14-4root7
=> root7-4
=> 5(root7+2)-2root7(root7+2)
=> 5root7+10-14-4root7
=> root7-4
2010-06-12 6:16 pm
5â7 + 10 - 14 - 4â7 = â7 - 4
2010-06-12 6:16 pm
(5-2â7)(â7+2)
=5â7 + 10 - 2xâ7xâ7 - 4â7
=â7(5-4) + 10 - 2x7
=â7 + 10 - 14
=2.646 + 10 - 14
= -1.354
=5â7 + 10 - 2xâ7xâ7 - 4â7
=â7(5-4) + 10 - 2x7
=â7 + 10 - 14
=2.646 + 10 - 14
= -1.354
收錄日期: 2021-05-01 13:13:29
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