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If a,b,c are sides an acute angle triang...

If `a,b,c` are sides an acute angle triangle satisfying `a^(2)+b^(2)+c^(2)=6` then `(ab+bc+ca)` can be equal to

A

3

B

4

C

5

D

7

Text Solution

Verified by Experts

The correct Answer is:
B, C
`:' ab+bc+ca le (a^(2)+b^(2)+c^(2))` for all `a, b, c epsilon R`
`implies ab+bc+ca lt 6`
Again `a^(2) gt b^(2)+c^(2)-2bc ( :' cos Alt 1)`
`:. (a^(2)+b^(2)+c^(2))/2 lt (ab+bc+ca)`
`implies ab+b+cagt 3` So, (B) & (D)
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