Question

Please help me with these

Answer 1

Answer:

Hello friend...I can solve question 4 for you, I'm unable to solve question 3

Step-by-step explanation:

Given that 8×4^x-9×2^x+1=0

Now this can be written as

8×2^(x)(2)-9×2^x+1=0

now as value of 2^x=y

so, 8×y^2-9×y+1=0

So now this is a quadratic equation .

8y^2-9y+1=0

this can be written as

8y^2-8y-y+1=0

so, 8y(y-1)-1(y-1)=0

so, (8y-1)(y-1)=0

therefore y= 1/8 or 1

Now as y was 2^x

therefore 2^x=1 or 1/8

now first take 2^x as 1

so 2^x=1

so therefore x=0 [x=0 because anything to power 0 equals 1]

and by 2^x=1/8

we get x=-3

so now x=0,-3

now check whether the both value of x satisfy this equation

so 8×4^x-9×2^x+1=0

now by x at 0

8×1-9×1+1=0

so, -1+1=0

so 0=0

therefore x=0 is a solution

now by x at -3

8×1/64-9×1/8+1=0

so, 1/8-9/8+1=0

so, -8/8+1=0

so, -1+1=0

so 0=0

therefore x=-3 is also a solution

so final answer:- x=0,-3

I HOPE THIS WILL HELP YOU MY FRIEND...IF YOU FIND IT CORRECT PLZ MARK ME AS BRAINLIEST