Pls answer this...its very important for me...i have an exam coming up...and this 2 questions will come up so pls help. I WILL MARK AS BRAINLIEST WHOEVER ANSWERED RIGHT.
1. Find the value of x
a) [tex]\frac{4^{2x} }{4^{x} } = 64[/tex]
b) [tex](2^{2x} )^{3} = 64[/tex]

Respuesta :

Answer:

a. x = 3

b. x = 3

Step-by-step explanation:

Given

[tex]\frac{4^{2x}}{4^x} = 64[/tex]

[tex](2^{2x}) = 64[/tex]

Required

Find x

Solving [tex]\frac{4^{2x}}{4^x} = 64[/tex]

From laws of indices;

[tex]\frac{a^{m}}{a^n} = a^{m-n}[/tex]

So;

[tex]4^{2x-x} = 64[/tex]

[tex]4^{x} = 64[/tex]

Write 64 in base of 4

[tex]4^{x} = 4^3[/tex]

From laws of indices;

[tex]if\ x^a = x^b;\ then\ a = b[/tex]

So; x = 3

Solving [tex](2^{2x}) = 64[/tex]

Write 64 as a base of 2

[tex](2^{2x}) = 2^6[/tex]

[tex]if\ x^a = x^b;\ then\ a = b[/tex]

[tex]2x = 6[/tex]

Divide both sides by 2

[tex]\frac{2x}{2} = \frac{6}{2}[/tex]

[tex]x = 3[/tex]