Step-by-step explanation:
Q6
answer A, as x² is the regular parabolic curve up. and x²-3 just shifts this curve down by 3 units. and that is what we need, as the extreme point of the curve is a bit below the x-axis, and therefore has a negative y value.
Q7
answer C, as this curve is the complete opposite of the curve in Q6.
it is the regular parabolic curve but down. that means -x².
but the extreme point is a bit above the x-axis (and has therefore a positive y value). -x²+3 shifts the parabolic curve up by 3 units.
Q8
answer A again. the functional values are only positive (the whole curve is above the x-axis). so, C and D are therefore wrong.
and between A and B we need to remember, that a negative exponent means 1/...
in case of B 1/(2^x).
and that would mean for large positive x we would get very small values for y.
but we see the opposite. for large x we also get large y.
so, it is 2^x (answer A).
