p= kq^3. when p= 9 , q= 3 a) calculate the value of k b) calculate p when q= 6 c) calculate p when q= 1 d) calculate q when p= 576

Respuesta :

Answer:

see explanation

Step-by-step explanation:

Given

p = kq³

(a)

To find k use the condition when p = 9, q = 3, that is

9 = k × 3³ = 27k ( divide both sides by 27 )

k = [tex]\frac{9}{27}[/tex] = [tex]\frac{1}{3}[/tex]

p = [tex]\frac{1}{3}[/tex] q³ ← equation of variation

(b)

  When q = 6, then

p = [tex]\frac{1}{3}[/tex] × 6³ = [tex]\frac{1}{3}[/tex] × 216 = 72

(c)

When q = 1, then

p = [tex]\frac{1}{3}[/tex] × 1³ = [tex]\frac{1}{3}[/tex]

(d)

When p = 576 , then

576 = [tex]\frac{1}{3}[/tex] q³ ( multiply both sides by 3 )

1728 = q³ ( take the cube root of both sides )

q = [tex]\sqrt[3]{1728}[/tex] = 12