How did the cobe mission and wmap mission provided evidence for the big bang theory?

The COBE mission and WMAP mission provided evidence for the Big Bang Theory by finding the cosmic background microwave radiation that is the remnants of the energy from the Big Bang. I am hoping that this answer has satisfied your query and it will be able to help you in your endeavor, and if you would like, feel free to ask another question.

COBE or Cosmic Background Explorer was launched in November 1989 to take precise measurements of the cosmic microwave background, faint radiations present ever where considered to be remnant of Big Bang. The radiation has average temperature of about 3 K and wavelength ranging from 100μm to 1 cm. The operation of the explorer was terminated in 1993.

Thereafter, WMAP (Wilkinson Microwave Anisotropy Probe) continued to explore more about the cosmos from 2001 to 2010. The probe measured the temperature difference across the sky in CMB. The data collected from the probe successfully led to the formation of standard model of cosmology.

i don't know that i agree with that but what's the question ?