 Quote by cstvlr
no its in an equation form,
C(x) = [(9-x) + 1.25sqrt( x^2 + 36 )], where C(x) is a function.
and they're trying to solve for x, so they used the method above, and I know how to solve it, but I lost it when they used let x = 3( t - 1/t )
|
x = 3( t - 1/t ) ⇒ x
2 = 9( t - 1/t )
2
∴√(36+x
2)=√(36+9(t- 1/t)
2), how does that turn into an expression like √(a+b)
2?
I do not think there rule per se for using that substitution though.