help how to get the critical value (1.96)

[restive dagger]

Correct me if i'm wrong but 1.96 comes from integrating the function e^-x^2/sqrt(pi) from -a to a (a is found to be 1.96) where the area is 95% the total area of the function

[restive dagger]

i can't remember the function exactly

basically it's the numerical value for 95% of the area under the normal proability curve

sorry the vocabulary for this evades me now

[near brook]

the curve you named doesnt have the correct standard deviation, it should be e^(-x^2/2)/√(2π)

you have it correct that $\int_{-1.96}^{1.96}\frac{e^{-\frac{x^2}2}}{\sqrt{2\pi}}\dd{x}=0.95$

[coarse roost]

mtt07734

[near brook]

the number "1.96" comes from figuring out what gets you that 95% exactly
its not simplifiable, but its ≈1.95996398
notice there it rounds to 1.9600 nicely

[restive dagger]

Ah thanks

[near brook]

np

.solved