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प्रश्न
If one root of the equation `2x^2+ax+6=0` 2 then a=?
(a)7 (b)-7 (c) 7/2 (d)-7/2
उत्तर
(b) -7
It is given that one root of the equation `2x^2+ax+6=0 is 2`
∴` 2xx2^2+axx2+6=0`
⇒ `2a+14=0`
⇒` a=-7`
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