SOLUTION: limit x->0 (e^x^2 - e^x^3)/3x^2 please show steps. thanks.

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Question 1154021: limit x->0 (e^x^2 - e^x^3)/3x^2
please show steps. thanks.

Found 2 solutions by MathLover1, ikleyn:
Answer by MathLover1(20850) About Me  (Show Source):
Answer by ikleyn(52847) About Me  (Show Source):
You can put this solution on YOUR website!
.

Start from standard expansion of Calculus for e%5Et

    e%5Et = 1 + t + t%5E2%2F2 + t%5E3%2F3%21 + . . .               (1)



Substitute one time  t = x^2  into expansion  (1)  to get

    e^(x^2) = 1 + x^2 + x%5E4%2F2 + x%5E6%2F6 + . . .         (2)



Substitute next time  t = x^3  into expansion  (1)  to get

    e^(x^3) = 1 + x^3 + x%5E6%2F2 + x%5E9%2F6 + . . .         (3)



Subtract (3) from (2). You will get

    e^(x^2) - e^^(x^3) = x^2 - x^3 + the terms of the converging series with degrees of  "x"  higher than or equal to 4.


Therefore

    %28e%5E%28x%5E2%29+-+e%5E%28x%5E3%29%29%2F%28x%5E2%29 = 1 - x + the terms of the converging series with degrees of  "x"  higher than or equal to 2.     (4)


Thus, when you take the limit at x--> 0 of  %28e%5E%28x%5E2%29+-+e%5E%28x%5E3%29%29%2F%283x%5E2%29,  you will get  1%2F3.     ANSWER


The rest of the terms contribute 0 (zero) to this limit.

Solved.

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I wrote this post, because arguments of @MathLover1 are   I N V A L I D.


Had I answered this question as @MathLover1 did it,  with expressions   0%2F0   on the way,  I would loose my reputation  FOREVER
in the eyes of my teachers.