₦airaland Forum

HellVictorinho:
X is 40°
AEB =180-(70+60+20)=30°
BDE=90°
X=180-(90+30+20)=40°
You can't use sine rule without any given side.

mathefaro:
How do you know that BDE is 90°? That has been the only missing piece of the puzzle. Every other angle of the triangle is so glaring

mathefaro:
How do you know that BDE is 90°? That has been the only missing piece of the puzzle. Every other angle of the triangle is so glaring

HellVictorinho:
It is perpendicular.

HellVictorinho:
X is 40°
AEB =180-(70+60+20)=30°
BDE=90°
X=180-(90+30+20)=40°
You can't use sine rule without any given side.

mathefaro:
can you kindly explain how?

mathefaro:
Sine rule? With no side at all? I'll really love to learn that o.

jackpot:
Please, kindly snap workings and post

MrEDUCATION:
Please and please, I need a clear and detailed explanation to these questions...

1) Which of the following is not a factor of 12⁴ - 5⁴

A. 7
B. 13
C. 49
D. 169
E. 216
Difference of two squares
(12²-5²)(12²+5²)
(12+5)(12-5)(169)
(17)(7)(169)
The answer is 216 because it can't divide the product of 17x7x169 without remainder


2) A quadrant of a circle of radius 6cm is cut away from each corner of a rectangle 25cm long and 18cm wide. Find the perimeter of the remaining figure.
A) 38
B) 38+12π
C) 86 -12π
D) 86 -6π
Area of rectangle=25x2+18×2=86cm
4quadrant =one circle=2πx6=12π
Perimeter=86+12π-(4x2radius)
=86-8x6+12π
=38+12π


3) ln root 216 - ln root 125 - ln root 8 divided by
2(ln 5 - ln 3)
.
A. -3/2
B. 3
C. 3/4
D. -3/2
E. ln6 - 2ln5

TYPE THIS WELL
4) Find dy/dx,
if y=6x × 3 -5x × 2+1/3x × 2
TYPE THUS WELL

Mrshape:
Here is the suggested solution

dejt4u:
here I got x to be 20°

dejt4u:
here I got x to be 20°

Mrshape:
Here is the suggested solution

mathefaro:
like I said earlier, you've made a lot of assumptions which you ought not to including the fact that those sides you labelled K are equal. I could also make some assumptions totally different from yours and get another answer. I still believe there's a piece missing from the question

Mrshape:
Because I got that before but when I solved again I got another thing, the solution is to long and am too lazy to check for errors

dejt4u:
those are not assumptions but facts.. We have 2 different isosceles triangles in that shape if you observe very well

mathefaro:
like I said earlier, you've made a lot of assumptions which you ought not to including the fact that those sides you labelled K are equal. I could also make some assumptions totally different from yours and get another answer. I still believe there's a piece missing from the question

Mrshape:
Sir 8 don't make any assumption.
What ever you don't get let me know their is a proof for all my steps

mathefaro:
Oh Oh, my bad, I just saw what he did. I feel so embarrassed right now. Although I've spotted an error in his work

mathefaro:
I have pointed out an anomaly in your work in the post above. Check it out

mathefaro:
I don't think 49 is also a factor

mathefaro:
I don't think 49 is also a factor

Mrshape:
Thanks that's were missed it.
I was supposed to get 20° as the answer

jackpot:
Initially, I used construction and it gave 20° though I wasn't satisfied because construction gives approximate results.

I got 20° too, using sine rule mostly, and cosine rule once on triangle CDE, but solution is dependent on calculator and trig identities. I set AB=1 for obvious reasons since scaling won't affect angles.

I even got the bonus fact that CE=AB.�

Mrshape:
Alright
Are you a maths student or a maths professor

dejt4u:
He lectures maths

jackpot:
Initially, I used construction and it gave 20° though I wasn't satisfied because construction gives approximate results.

I got 20° too, using sine rule mostly, and cosine rule once on triangle CDE, but solution is dependent on calculator and trig identities. I set AB=1 for obvious reasons since scaling won't affect angles.

I even got the bonus fact that CE=AB.�

Engrkawu:
Someone please help on this

bokunrawo:
Guys help

MrEDUCATION:
@ Mrshape


Thank you Sir!

The other questions were written just the way I typed it...