Edexcel C1 Core Maths January 2007 Q8a,b,c

[Peacock2613]

how do you know it's an perpendicular line, because before looking at the video i subsititued -3 instead of 1/3. the question didn't say anything about perpendicular line. Are there any way you could find out if its perpendicular line of not in the question. Sorry im just confused.

[ExamSolutions]

@Peacock2613 It says a normal to the line. All normals have a perpendicular gradient to another line.

[Peacock2613]

@ExamSolutions Thank you, sorrry for bothering , just to clarify if the gradient is a positive like for example 5 do you have to make chnage into 1/5 or something:S

[ExamSolutions]

@Peacock2613 No -1/5. Switch the sign and invert the fraction. Look at my tutorials on coordinate geometry, perpendicular lines for more information.

[Peacock2613]

@ExamSolutions okay, Thank you for you time :)

[lpspgameplay]

i am so confused with:

when you do Dy/Dx of some equation

Does the derivate give gradient of normal or tangent?

[ExamSolutions]

@lpspgameplay gradient of the tangent. Check out the video tutorials on this.

[lpspgameplay]

@ExamSolutions ah thank you! so to find the normal gradient its perpedicular so has to times to be -1 right?

[ExamSolutions]

@lpspgameplay Yes

[addicted92]

omg u sooo ROC!

o got a) rite. but then i didnt knw wot 2 do.

THANK U!

=D

[jagexbluedragonarmy]

great explanations learn more off youtube then skl tbh

[Dippazncream]

yh ur so right! u took the words right out my mouth.

[addicted92]

total HI5 here.

we should all learn on youtube instead.

teachers rnt useful.