How would I type this function correctly?

How would I type this correctly into matlab? This is what I came up with but it doesn't work.

(atan(2)+log7(150)-4sqrt(88))/((abs)sin(4)-1.4^1.4)

Answer 1

[the cyclist]

I guess it is fair to say that you have not really learned basic MATLAB syntax at all.

I would recommend starting to learn the basics by going through the free MATLAB Onramp tutorial. If you don't start learning, then you will need to ask every MATLAB coding question here, forever.

That being said, here are the main things that you need to fix in your code:

There is no log7() function in MATLAB. It has logs for base 2, e, and 10. But you can use the rules of logarithms to get what you want:

x = 150;
log(x) / log(7)

ans = 2.5750

There is no function to take the 4th root of a value. But you can just do this as the 1/4 power:

x = 88;
x^(1/4)

ans = 3.0628

Because you wanted the absolute value of the sum of the two terms, you should have written

abs(sin(4)-1.4^1.4)

ans = 2.3585

Now, maybe you can put this all together?

[John]

Thank you, Yes, I am very new to matlab and I appreciate the advice. I put it together and I think I've got it. I was definetly having issues with the sqrt and Log.

[John D'Errico]

+1 of course, but with a couple of comments. 4th root can be obtained from the nthroot function.

nthroot(16,4)

ans = 2

Oh, and be careful, in that too often new users don't realize that sin assumes RADIANS for an argument. So is that 4 meant to be degrees, or radians?

sin(4) % radians

ans = -0.7568

sind(4) % degrees

ans = 0.0698

It very much matters. You use sind and cosd (and atand, etc.) for degree inputs. Or you can convert radians to degrees or the other way around. It is just a scale factor of 180/pi for the transformation.

[the cyclist]

Today I learned the nthroot function. Thanks for adding the additional info. It's easy to forget the simple assumptions.

Answer 2

[Image Analyst]

@John To write this:

try this:

logTerm = log(150) / log(7); % Same as log to the base 7 of 150.
numerator = atan(2) + logTerm - nthroot(88, 4);
denominator = abs(sin(4) - 1.4 ^ 1.4);
output = numerator / denominator

output = 0.2626

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