Math, asked by shishir38, 1 year ago

Solve this math!! Only for intelligent people

Attachments:

QGP: You got your answer, Why are you posting it again?
shishir38: But I didnt get the answer then! But u gave it so I cant delete the question
QGP: Ah okay. Anyways
shishir38: Will you solve other questions??
QGP: I will try. Currently solving another question
shishir38: Ok but see my questions afterwards
QGP: Sure
shishir38: or shall I send my question in whatsapp or instagram if u want
QGP: No I will check myself.
shishir38: ok

Answers

Answered by JinKazama1
7
Final Answer : 2<k<4

Steps:
1)
 {x}^{2}  - 2(4k - 1)x + 15 {k}^{2}  - 2k - 7 &gt; 0
This quadratic equation is always positive,
=> Graph is upward parabola which doesn't cut x - axis
=> D < 0
=>
 {(2(4k - 1))}^{2}  - 4 \times \\  (15 {k}^{2}  - 2k - 7) &lt; 0 \\  =  &gt; 64 {k}^{2}  - 32k + 4 - 60 {k}^{2}  + 8k + 28 &lt; 0 \\  =  &gt; 4 {k}^{2}  - 24k + 32 &lt; 0 \\  =  &gt;  {k}^{2}  - 6k + 8 &lt; 0 \\  =  &gt; (k - 4)(k - 2) &lt; 0 \\  =  &gt; 2 &lt; k &lt; 4
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