. The number of real roots of the equation e⁴ˣ + e³ˣ – 4e²ˣ – eˣ + 1 = 0 is equal to…………..
. The number of real roots of the equation e⁴ˣ + e³ˣ – 4e²ˣ – eˣ + 1 = 0 is equal to…………..
Asked by Shiksha User
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1 Answer
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e? +e³? −4e²? −e? +1=0
Divide by e²?
⇒ (e²? +e? ²? )− (e? +e? )−4=0
Put e? +e? =t>0
e²? +e? ²? +2=t²
t²−2−t−4=0
⇒t²−t−6=0
⇒t=3, t=−2 but t≠−2
⇒t=3
⇒e? +e? =3
Number of solution=2
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