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    Y=2*3^x
    When X = 0 Y= 2

    When Y = 0 0 = 2*3^x
    I cannot solve the Y part, can somebody help me please?

    Thank you
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    (Original post by Jusst Haris)
    Y=2*3^x
    When X = 0 Y= 2

    When Y = 0 0 = 2*3^x
    I cannot solve the Y part, can somebody help me please?

    Thank you
    That equation is invalid, since  \log(x) > 0 for all  x .

    There is no value of  x that will satisfy that equation, in other words.

    Is that the actual question though? Can I see what the actual question is?
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    (Original post by kingaaran)
    That equation is invalid, since  \log(x) > 0 for all  x .

    There is no value of  x that will satisfy that equation, in other words.

    Is that the actual question though? Can I see what the actual question is?
    Sketch the curve y = 2 * 3^x, stating the co-ordinates of any intersections with the axis.

    One of the intersections is at (0,2) i assumed that there should be another one how do i work that out?
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    (Original post by Jusst Haris)
    Sketch the curve y = 2 * 3^x, stating the co-ordinates of any intersections with the axis.

    One of the intersections is at (0,2) i assumed that there should be another one how do i work that out?
    Ah!

    Okay, so you tried to work out where it crossed the  x axis.

    And when you did that you ended up with  2(3^x) = 0 , which cannot be solved.

    Now the fact this equation has no solutions, what does it tell you about the curve? Does it cross the  x axis?

    Hint
    Consider graphs such as  y = \frac{1}{x} , which, if you try to do a similar thing, end up with the same problem
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    (Original post by kingaaran)
    Ah!

    Okay, so you tried to work out where it crossed the  x axis.

    And when you did that you ended up with  2(3^x) = 0 , which cannot be solved.

    Now the fact this equation has no solutions, what does it tell you about the curve? Does it cross the  x axis?

    Hint
    Consider graphs such as  y = \frac{1}{x} , which, if you try to do a similar thing, end up with the same problem
    Oh Okay i understand thank you, it's an asymptote, it gets closer to x - axis but never touches.
    Does this mean the only co-ordinate i can label is (0,2)?
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    (Original post by Jusst Haris)
    Oh Okay i understand thank you, it's an asymptote, it gets closer to x - axis but never touches.
    Does this mean the only co-ordinate i can label is (0,2)?
    Indeed
 
 
 
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