F.4 Mathematics Quadratic equations 求救

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( p2 + 4 )x2 + 4 - 10x = 0

Prove that for all value of p, the equation has no real roots

b^2-4ac < 0
(-10)^2-4(p^2+4)4 < 0
100-(16p^2+64) < 0
-16p^2+36 <0
p=-1.5 or 1.5
so when the value of p is -1.5 or 1.5 , the equation has no real roots.
我覺得大家誤解了題目
題目要在equation has no real roots的情況下 找出所有value of p
而非去prove that all value of p , the equation has no real roots呢件事
用F4思維解決F4問題好過庸人自擾