Please can someone show me their working on these, as I'd really like to know where I went wrong.


Answer:
C
Step-by-step explanation:
You were on the right track, but 3-2 = 1, so the exponent of (x-4) is 1.
Answer:
C and B
Step-by-step explanation:
(6)
[tex]\frac{(x-4)^3(3x+6)}{(x-4)^2}[/tex]
Cancel (x - 4)³ on numerator with (x - 4)² on denominator
leaving (x - 4) on numerator and 1 on denominator
= (x - 4)(3x + 6) → C
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Using the rule of exponents
[tex]a^{m}[/tex] × [tex]a^{n}[/tex] = [tex]a^{(m+n)}[/tex] , then
4a² × 7[tex]a^{\frac{1}{2} }[/tex]
= 4 × 7 × a² × [tex]a^{\frac{1}{2} }[/tex]
= 28 × [tex]a^{\frac{4}{2} }[/tex] × [tex]a^{\frac{1}{2} }[/tex]
= 28 × [tex]a^{(\frac{4}{2}+\frac{1}{2}) }[/tex]
= 28[tex]a^{\frac{5}{2} }[/tex] → B