Where does the mark scheme get these numbers from?

Thread starter TheePhysicsStudent
Start date Mar 11, 2024
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Numbers

AI Thread Summary

The discussion centers on the derivation of a quadratic equation in a mark scheme, specifically addressing an error in factorization. A user realizes that the quadratic formula was the correct approach rather than the attempted factorization. Another participant points out that the transition from the equation Sin^2(θ) + Sin(θ) - 1 = 0 to Sin(θ)(Sin(θ) - 1) = 0 is incorrect. They suggest distributing the terms to verify the equality. The conversation highlights the importance of accurate mathematical manipulation in solving equations.

Mar 11, 2024

TheePhysicsStudent

Homework Statement: practicing some Trigonmetric identities and equations questions, and unsure how the mark scheme managed to reach what sin theta is equal to (Q 4B)

Relevant Equations: sin^2 x + cos^2 x =1

Q4B

Mark scheme

My working

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Mar 11, 2024

TheePhysicsStudent

NVM guys, i just realised that the quadratic formula was used! Sorry for anyone who may have wasted time

Mar 11, 2024

WWGD

Science Advisor

Homework Helper

Your factorization, 3 lines from the bottom, is incorrect
The step from[Edit]
## Sin^2(\theta)+Sin(\theta)-1=0## , to
##Sin(\theta)[Sin(\theta)-1]=0##
Doesn't follow.
Distribute the terms in the bottom expression to test if they're equal.

Last edited: Mar 11, 2024

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