notation query

[woeful trail]

I appreciate that y' means dy/dx, specifically wrt x, but I often write stuff like y'(1) to say dy/dx at x=1

or i might even say y(x), is that alright? i do edexcel fm

[round flax]

y'(1) is okay

[white ore]

why do you appreciate that y' means dy/dx

what favour has it done you

[woeful trail]

💀
today i found out that y' specifically means w.r.t x. I thought it was just differential before

[woeful trail]

thanks, w.b. y(x), y'(x), y''(x) etc